Present Perfect

El objetivo de este blog es copiar la teoría de los temas vistos en clase de Inglés III para tener la información de una manera ordenada que nos permita estudiar de una manera sencilla.

Por favor hacer un esfuerzo por entender la explicación en inglés y sólo si le queda alguna duda lea la explicación en español.

Para hacer este blog se tomó la información de las páginas www.englishclub.com y www.mansioningles.com

Present Perfect Tense

I have sung

The present perfect tense is a rather important tense in English, but it gives speakers of some languages a difficult time. That is because it uses concepts or ideas that do not exist in those languages. In fact, the structure of the present perfect tense is very simple. The problems come with the use of the tense. In addition, there are some differences in usage between British and American English.

How do we make the Present Perfect Tense?

The structure of the present perfect tense is:

subject	+	auxiliary verb	+	main verb
		have		past participle

Here are some examples of the present perfect tense:

	subject	auxiliary verb		main verb
+	I	have		seen	ET.
+	You	have		eaten	mine.
-	She	has	not	been	to Rome.
-	We	have	not	played	football.
?	Have	you		finished?
?	Have	they		done	it?

Contractions with the present perfect tense

When we use the present perfect tense in speaking, we usually contract the subject and auxiliary verb. We also sometimes do this when we write.

I have	I've
You have	You've
He has She has It has John has The car has	He's She's It's John's The car's
We have	We've
They have	They've

Here are some examples:

• I've finished my work.
• John's seen ET.
• They've gone home.

He's or he's??? Be careful! The 's contraction is used for the auxiliary verbs have and be. For example, "It's eaten" can mean:

• It has eaten. [present perfect tense, active voice]
• It is eaten. [present tense, passive voice]

It is usually clear from the context.

How do we use the Present Perfect Tense?

This tense is called the present perfect tense. There is always a connection with the past and with the present. There are basically three uses for the present perfect tense:

1. experience
2. change
3. continuing situation

1. Present perfect tense for experience

We often use the present perfect tense to talk about experience from the past. We are not interested in when you did something. We only want to know if you did it:

I have seen ET. He has lived in Bangkok. Have you been there? We have never eaten caviar.
past	present	future
!!!
The action or state was in the past.	In my head, I have a memory now.

Connection with past: the event was in the past.
Connection with present: in my head, now, I have a memory of the event; I know something about the event; I have experience of it.

2. Present perfect tense for change

We also use the present perfect tense to talk about a change or new information:

I have bought a car.
past	present	future
-	+
Last week I didn't have a car.	Now I have a car.

 

John has broken his leg.
past	present	future
+	-
Yesterday John had a good leg.	Now he has a bad leg.

 

Has the price gone up?
past	present	future
+	-
Was the price $1.50 yesterday?	Is the price $1.70 today?

 

The police have arrested the killer.
past	present	future
-	+
Yesterday the killer was free.	Now he is in prison.

Connection with past: the past is the opposite of the present.
Connection with present: the present is the opposite of the past.

Americans do not use the present perfect tense so much as British speakers. Americans often use the past tense instead. An American might say "Did you have lunch?", where a British person would say "Have you had lunch?"

3. Present perfect tense for continuing situation

We often use the present perfect tense to talk about a continuing situation. This is a state that started in the past and continues in the present (and will probably continue into the future). This is a state (not an action). We usually use for or since with this structure.

I have worked here since June. He has been ill for 2 days. How long have you known Tara?
past	present	future
The situation started in the past.	It continues up to now.	(It will probably continue into the future.)

Connection with past: the situation started in the past.
Connection with present: the situation continues in the present.  

For & Since with Present Perfect Tense

We often use for and since with the present perfect tense.

• We use for to talk about a period of time - 5 minutes, 2 weeks, 6 years.
• We use since to talk about a point in past time - 9 o'clock, 1st January, Monday.

for	since
a period of time	a point in past time
	x------------
20 minutes	6.15pm
three days	Monday
6 months	January
4 years	1994
2 centuries	1800
a long time	I left school
ever	the beginning of time
etc	etc

Here are some examples:

• I have been here for 20 minutes.
• I have been here since 9 o'clock.
• John hasn't called for 6 months.
• John hasn't called since February.
• He has worked in New York for a long time.
• He has worked in New York since he left school.

For can be used with all tenses. Since is usually used with perfect tenses only.

Present Perfect (en español)

El tiempo Present Perfect se usa para hablar de acciones comenzadas en el pasado y que aún continúan en el presente. Por ejemplo:

I have been here since Monday.
He estado aquí desde el lunes.

Para formarlo, se usa el auxiliar HAVE, conjugado para la persona correspondiente (cambia solamente para la tercera persona del singular), seguido del participio pasado, que es igual para todas las personas.

Observe a continuación la conjugación del verbo SER.

TO BE
I	have been
You	have been
He	has been
She	has been
It	has been
We	have been
You	have been
They	have been

Para los verbos regulares, el participio pasado se forma tomando el propio verbo y agregando "ed", o "d" si termina en vocal. Si termina en "y", se cambia por "ied".

We have played tennis for two hours.
Hemos jugado tenis por dos horas.

She has arrived late again.
Ha llegado tarde de nuevo.

You have studied a lot.
Has estudiado mucho.

Los verbos irregulares tienen su propio participio pasado y la única manera de aprenderlos es memorizarlos. Normalmente son los que aparecen en la tercera columna de los listados de verbos irregulares en los diccionarios de inglés.

Por ejemplo el participio pasado del verbo TO SEE (ver) es "seen". Siempre es igual para todas las personas.

We have seen many people around here.
Hemos visto mucha gente por aquí.

She has seen many people around here.
Ella ha visto mucha gente por aquí.

Preguntas en Present Perfect

Para realizar preguntas usando este tiempo, se usa HAVE (conjugado para la persona correspondiente), seguido del sujeto, luego el participio pasado y finalmente el resto de la oración.

Have you had lunch?
Has almorzado? 

Forma negativa en Present Perfect

La forma negativa se compone del auxiliar HAVE en su forma negativa (conjugado para la persona correspondiente), seguido del participio pasado, que es igual para todas las personas.

I haven't seen him yet.
Aún no lo he visto. 

Lista de verbos irregulares (participio pasado) 

Presentamos aquí una pequeña lista de algunos verbos irregulares con su participio pasado. Intente recordarlos!

INFINITIVO	PARTICIPIO PASADO
go (ir)	gone
have (tener)	had
write (escribir)	written
read (leer)	read
catch (atrapar)	caught
fall (caer)	fallen
hear (escuchar)	heard
see (ver)	seen
say (decir)	said
give (dar)	given
know (saber)	known

Present Perfect vs. Simple Past
No se debe confundir el tiempo Present Perfect con el tiempo Simple Past. Observe la diferencia de significado entre estas oraciones:

I have just had lunch.
Recién he almorzado. (es una acción comenzada en el pasado y recientemente terminada)

I had lunch five hours ago.
Almorcé hace cinco horas. (es una acción completamente en el pasado).

El Present Perfect sugiere una relación entre el presente actual y el pasado. En cambio, el Simple Past siempre hace referencia al pasado. Por eso, cuando se usa Simple Past, se debe indicar cuándo tuvo lugar la acción.

IRREGULAR VERBS

Presentamos aquí una lista de verbos irregulares. Por cada verbo se incluye:

• el infinitivo
• la forma del Simple Past (Pasado Simple, por ejemplo: I arrived yesterday)
• el past participle (Participio pasado, que se utiliza en el tiempo Present Perfect, por ejemplo: I have broken a glass)
• su traducción al español

Los verbos regulares forman el Simple Past y el Past Participle agregando -ed al infinitivo. Los verbos irregulares no siguen esta regla y deberás aprenderlos de memoria.

También hemos compilado otras listas de verbos:
Verbos para niveles básicos
Verbos para niveles avanzados

Infinitive	Simple Past	Past Participle	Spanish
arise	arose	arisen	surgir
be	was / were	been	ser
beat	beat	beaten	golpear
become	became	become	convertirse
begin	began	begun	comenzar
bet	bet/betted	bet/betted	apostar
bite	bit	bitten	morder
bleed	bled	bled	sangrar
blow	blew	blown	soplar
break	broke	broken	romper
bring	brought	brought	traer
build	built	built	construir
buy	bought	bought	comprar
catch	caught	caught	atrapar
choose	chose	chosen	elegir
come	came	come	venir
cost	cost	cost	costar
creep	crept	crept	arrastrarse
cut	cut	cut	cortar
deal	dealt	dealt	dar, repartir
do	did	done	hacer
draw	drew	drawn	dibujar
dream	dreamt/dreamed	dreamt/dreamed	soñar
drink	drank	drunk	beber
drive	drove	driven	conducir
eat	ate	eaten	comer
fall	fell	fallen	caer
feed	fed	fed	alimentar
feel	felt	felt	sentir
fight	fought	fought	pelear
find	found	found	encontrar
flee	fled	fled	huir
fly	flew	flown	volar
forget	forgot	forgotten	olvidar
forgive	forgave	forgiven	perdonar
forsake	forsook	forsaken	abandonar
freeze	froze	frozen	congelar
get	got	got	tener, obtener
give	gave	given	dar
go	went	gone	ir
grind	ground	ground	moler
grow	grew	grown	crecer
hang	hung	hung	colgar
have	had	had	tener
hear	heard	heard	oír
hide	hid	hidden	esconderse
hit	hit	hit	golpear
hold	held	held	tener, mantener
hurt	hurt	hurt	herir, doler
keep	kept	kept	guardar
kneel	knelt	knelt	arrodillarse
know	knew	known	saber
lead	led	led	encabezar
learn	learnt/learned	learnt/learned	aprender
leave	left	left	dejar
lend	lent	lent	prestar
let	let	let	dejar
lie	lay	lain	yacer
lose	lost	lost	perder
make	made	made	hacer
mean	meant	meant	significar
meet	met	met	conocer, encontrar
pay	paid	paid	pagar
put	put	put	poner
quit	quit/quitted	quit/quitted	abandonar
read	read	read	leer
ride	rode	ridden	montar, ir
ring	rang	rung	llamar por teléfono
rise	rose	risen	elevar
run	ran	run	correr
say	said	said	decir
see	saw	seen	ver
sell	sold	sold	vender
send	sent	sent	enviar
set	set	set	fijar
sew	sewed	sewn/sewed	coser
shake	shook	shaken	sacudir
shine	shone	shone	brillar
shoot	shot	shot	disparar
show	showed	shown/showed	mostrar
shrink	shrank/shrunk	shrunk	encoger
shut	shut	shut	cerrar
sing	sang	sung	cantar
sink	sank	sunk	hundir
sit	sat	sat	sentarse
sleep	slept	slept	dormir
slide	slid	slid	deslizar
sow	sowed	sown/sowed	sembrar
speak	spoke	spoken	hablar
spell	spelt/spelled	spelt/spelled	deletrear
spend	spent	spent	gastar
spill	spilt/spilled	spilt/spilled	derramar
split	split	split	partir
spoil	spoilt/spoiled	spoilt/spoiled	estropear
spread	spread	spread	extenderse
stand	stood	stood	estar de pie
steal	stole	stolen	robar
sting	stung	stung	picar
stink	stank/stunk	stunk	apestar
strike	struck	struck	golpear
swear	swore	sworn	jurar
sweep	swept	swept	barrer
swim	swam	swum	nadar
take	took	taken	tomar
teach	taught	taught	enseñar
tear	tore	torn	romper
tell	told	told	decir
think	thought	thought	pensar
throw	threw	thrown	lanzar
tread	trode	trodden/trod	pisar
wake	woke	woken	despertarse
wear	wore	worn	llevar puesto
weave	wove	woven	tejer
weep	wept	wept	llorar
win	won	won	ganar
wring	wrung	wrung	retorcer
write	wrote	written	escribir

EXERCISES
En esta parte podrá aplicar lo aprendido, practicar y comprobar que recuerda tanto el vocabulario como la gramática de la lección. Si comete errores, se recomienda repasar los temas y volver a realizar los ejercicios.

Exercise 1

Complete los recuadros.
Score:
    

 

 

Exercise 2

Complete los recuadros usando el verbo entre paréntesis en Present Perfect o Simple Past.
1. Jane (stay) at home yesterday.
2. Your letter (arrive) two days ago.
3. I (live) here for ten years.
4. Last week we (go) to the cinema.
5. The game (start) . They are playing now.
6. I (phone) you at five and you weren't there.
7. I (lose) my watch, I can't find it.
8. Last month Sarah (travel) to Italy.
9. I (work) all day and now I'm tired.
10. We (buy) a new house last week.
Score:
    

Exercise 3

Elija la opción más adecuada para responder o terminar cada oración.
Did you study yesterday?
Yes, I have.
Yes, I did.
Have you ever been to London?
Yes, I was.
Yes, I have.
You have just made a cake,
haven't you?
didn't you?
What did you do last week?
I went to the cinema.
I have been to the cinema.
Did you watch TV last night?
Yes, I have.
Yes, I did.
Have you seen this programme before?
Yes, I did.
Yes, I have.
Has the plane landed?
Yes, it landed at 10.25.
Yes, it has landed at 10.25.
Has Richard washed his car?
No, he hasn't washed it for months.
No, he washed it yesterday.

Score:
   

Present Perfect Tense Quiz

1	Lindsay hasishave not been to France.	Click for answerhas
2	HaveHasIs you finished your homework?	Click for answerHave
3	They 's'es've gone to a rock concert.	Click for answer've
4	IsHaveHas you been to Japan?	Click for answerHave
5	We havehasare never eaten Mexican food.	Click for answerhave
6	Andrea has forgetforgettingforgotten her umbrella.	Click for answerforgotten
7	WasHasHave the sun come up?	Click for answerHas
8	The children have findis findinghave found the lost puppy.	Click for answerhave found
9	How long have you bebeenare a vegetarian?	Click for answerbeen
10	I haven't worked sinceforby last December.

 

First Conditional: real possibility

We are talking about the future. We are thinking about a particular condition or situation in the future, and the result of this condition. There is a real possibility that this condition will happen. For example, it is morning. You are at home. You plan to play tennis this afternoon. But there are some clouds in the sky. Imagine that it rains. What will you do?

IF	condition	result
	present simple	WILL + base verb
If	it rains	I will stay at home.

Notice that we are thinking about a future condition. It is not raining yet. But the sky is cloudy and you think that it could rain. We use the present simple tense to talk about the possible future condition. We use WILL + base verb to talk about the possible future result. The important thing about the first conditional is that there is a real possibility that the condition will happen. Here are some more examples (do you remember the two basic structures: [IF condition result] and [result IF condition]?):

IF	condition	result
	present simple	WILL + base verb
If	I see Mary	I will tell her.
If	Tara is free tomorrow	he will invite her.
If	they do not pass their exam	their teacher will be sad.
If	it rains tomorrow	will you stay at home?
If	it rains tomorrow	what will you do?

 

result	IF	condition
WILL + base verb		present simple
I will tell Mary	if	I see her.
He will invite Tara	if	she is free tomorrow.
Their teacher will be sad	if	they do not pass their exam.
Will you stay at home	if	it rains tomorrow?
What will you do	if	it rains tomorrow?

 

Sometimes, we use shall, can, or may instead of will, for example: If you are good today, you can watch TV tonight.

Second Conditional: unreal possibility or dream

The second conditional is like the first conditional. We are still thinking about the future. We are thinking about a particular condition in the future, and the result of this condition. But there is not a real possibility that this condition will happen. For example, you do not have a lottery ticket. Is it possible to win? No! No lottery ticket, no win! But maybe you will buy a lottery ticket in the future. So you can think about winning in the future, like a dream. It's not very real, but it's still possible.

IF	condition	result
	past simple	WOULD + base verb
If	I won the lottery	I would buy a car.

Notice that we are thinking about a future condition. We use the past simple tense to talk about the future condition. We use WOULD + base verb to talk about the future result. The important thing about the second conditional is that there is an unreal possibility that the condition will happen.
Here are some more examples:

IF	condition	result
	past simple	WOULD + base verb
If	I married Mary	I would be happy.
If	Ram became rich	she would marry him.
If	it snowed next July	would you be surprised?
If	it snowed next July	what would you do?

 

result	IF	condition
WOULD + base verb		past simple
I would be happy	if	I married Mary.
She would marry Ram	if	he became rich.
Would you be surprised	if	it snowed next July?
What would you do	if	it snowed next July?

 

Sometimes, we use should, could or might instead of would, for example: If I won a million dollars, I could stop working.

Third Conditional: no possibility

The first conditional and second conditionals talk about the future. With the third conditional we talk about the past. We talk about a condition in the past that did not happen. That is why there is no possibility for this condition. The third conditional is also like a dream, but with no possibility of the dream coming true.
Last week you bought a lottery ticket. But you did not win. :-(

	condition	result
	Past Perfect	WOULD HAVE + Past Participle
If	I had won the lottery	I would have bought a car.

Notice that we are thinking about an impossible past condition. You did not win the lottery. So the condition was not true, and that particular condition can never be true because it is finished. We use the past perfect tense to talk about the impossible past condition. We use WOULD HAVE + past participle to talk about the impossible past result. The important thing about the third conditional is that both the condition and result are impossible now.

Sometimes, we use should have, could have, might have instead of would have, for example: If you had bought a lottery ticket, you might have won.

Look at some more examples in the tables below:

IF	condition	result
	past perfect	WOULD HAVE + past participle
If	I had seen Mary	I would have told her.
If	Tara had been free yesterday	I would have invited her.
If	they had not passed their exam	their teacher would have been sad.
If	it had rained yesterday	would you have stayed at home?
If	it had rained yesterday	what would you have done?

 

result	IF	condition
WOULD HAVE + past participle		past perfect
I would have told Mary	if	I had seen her.
I would have invited Tara	if	she had been free yesterday.
Their teacher would have been sad	if	they had not passed their exam.
Would you have stayed at home	if	it had rained yesterday?
What would you have done	if	it had rained yesterday?

 

Zero Conditional: certainty

We use the so-called zero conditional when the result of the condition is always true, like a scientific fact.
Take some ice. Put it in a saucepan. Heat the saucepan. What happens? The ice melts (it becomes water). You would be surprised if it did not.

IF	condition	result
	present simple	present simple
If	you heat ice	it melts.

Notice that we are thinking about a result that is always true for this condition. The result of the condition is an absolute certainty. We are not thinking about the future or the past, or even the present. We are thinking about a simple fact. We use the present simple tense to talk about the condition. We also use the present simple tense to talk about the result. The important thing about the zero conditional is that the condition always has the same result.

We can also use when instead of if, for example: When I get up late I miss my bus.

Look at some more examples in the tables below:

IF	condition	result
	present simple	present simple
If	I miss the 8 o'clock bus	I am late for work.
If	I am late for work	my boss gets angry.
If	people don't eat	they get hungry.
If	you heat ice	does it melt?

 

result	IF	condition
present simple		present simple
I am late for work	if	I miss the 8 o'clock bus.
My boss gets angry	if	I am late for work.
People get hungry	if	they don't eat.
Does ice melt	if	you heat it?

 

Conditionals: Summary

Here is a chart to help you to visualize the basic English conditionals. Do not take the 50% and 10% figures too literally. They are just to help you.

probability		conditional	example	time
100%		zero conditional	If you heat ice, it melts.	any time
50%		first conditional	If it rains, I will stay at home.	future
10%		second conditional	If I won the lottery, I would buy a car.	future
0%		third conditional	If I had won the lottery, I would have bought a car.	past

 

Conditionals Quiz

1	What would you do if it will rainwould rainrained on your wedding day?	Click for answerrained
2	If she comes I willwouldwould have call you.	Click for answerwill
3	If I eat peanut butter I getwould getwould have gotten sick.	Click for answerget
4	What will you do if you failyou would failyou will fail the history exam?	Click for answerfail
5	If they had not takentakewould take the car I would have driven you.	Click for answertaken
6	If it snows will youwould youwould you have still drive to the coast?	Click for answerwill you
7	He would have gonegogoing with you if you had asked him.	Click for answergone
8	If I won a million dollars I would buywill buywould have bought my own airplane.	Click for answerwould buy
9	If I forget her birthday Andrea getswould getwould have gotten upset.	Click for answergets
10	Jacob will pick you up at school if it will rainrainsrained.	Click for answerrains

Conditionnel (en español)

Type 1 Conditionals

Las oraciones condicionales sirven para expresar situaciones que probablemente (o seguramente) ocurrirán en el futuro si se cumple la condición indicada.
Por ejemplo:

If the price comes down, more people will buy it.
Si el precio baja, más gente lo comprará.

A esta oración se la denomina oración condicional del primer tipo. Expresa una condición que es muy probable que se cumpla.

If + condición + consecuencia
If + Present + Future Simple

Estas oraciones se forman comenzando con IF y agregando la condición, expresada en tiempo presente. Luego, se agrega lo que ocurrirá si se cumple esa condición, expresado en tiempo futuro simple (con will).

If it rains, I will stay home.
Si llueve, me quedaré en casa.

If I have a headache, I will take an aspirin.
Si tengo dolor de cabeza, tomaré una aspirina.

If I am better tomorrow, I will go to work.
Si me siento mejor mañana, iré a trabajar.

Note que en el último ejemplo, a pesar de que se utiliza la palabra tomorrow el verbo después de if debe ir siempre en Presente. Es incorrecto decir If I will be better tomorrow.

Luego de if tambén es posible utilizar can.

If you can go, we will go with you.
Si tú puedes ir, nosotros iremos contigo.

La condición tambén puede ser negativa.

If it doesn't rain, we will go to the beach.
Si no llueve, iremos a la playa.

También es posible realizar preguntas con las oraciones condicionales.

What will you do if it rains?
¿Qué harás si llueve?

What will you do if you have a headache?
¿Qué harás si tienes dolor de cabeza?

Una variación del primer tipo de condicional consiste en utilizar el imperativo en la segunda parte:

If + condición + consecuencia
If + Present + Imperative

If the car stops, go to a garage.
Si el automóvil se detiene, vé a un garage.

If the telephone rings, do not answer it.
Si el teléfono llama, no lo atiendas.

Exercise 1

Complete los recuadros con los verbos que se encuentran entre paréntesis en el tiempo correcto. Use las formas cortas de los verbos siempre que sea posible.
1. If you (send) the letter today, it'll arrive tomorrow.
2. If you don't study, you (pass) the exam.
3. If it rains, we (stay) at home.
4. If it (be) sunny, we'll go to the beach.
5. If that shop (be) closed, we'll go to another one.
6. If you (want) , we'll go to the park.
7. If Adam (arrive) late, his father will be upset.
8. If you work hard, you (get) a bonus.
9. If it isn't expensive, I (buy) two.
10. If you (call) me, I won't answer the phone.
Score:
    

Exercise 2

Escriba la pregunta que corresponde a la respuesta dada, comenzando con What. Respete las mayúsculas, minúsculas y signos de puntuación.
La primera ya está respondida como ejemplo.

1.
We'll go to the cinema if it rains.
2.
If the weather is fine, I'll go to the park.
3.
If I see John, I will give him that book.
4.
If the museum is closed, they'll go to the library.
5.
If it's sunny, Peter and Alice will go to the zoo.
6.
If the telephone rings, I will answer it.
7.
If it's fine, they'll have a picnic.
8.
Sarah will take the train if the bus doesn't come.

Score:
   

Exercise 3

Elija la opción más adecuada para responder a la pregunta.

May I speak to Mr. Bean, please?
Hold the line, please.
Yes, it is.

What will you do tomorrow?
I will go to the park.
I think it was good.

What will you do if it rains?
I'm reading a book.
I'll read a book.

Where will you go if it's sunny?
Next week.
We'll go to the park.

What will they do if the bus doesn't come?
They'll take a taxi.
They took a taxi.

What will you do if John arrives?
I will talk to him.
No, I won't.

What did you do last week?
I will go the cinema.
I went to the cinema.

What did they eat yesterday?
They ate some meat.
They will eat some meat.

Score:

    

 

Type 2 Conditionals

Las oraciones condicionales del segundo tipo sirven para expresar situaciones que podrían ocurrir si se cumpliera una determinada condición hipotética.

Por ejemplo:

If I had a million dollars, I would buy a big house.
Si tuviera un millón de dólares, compraría una casa grande.

A esta oración se la denomina oración condicional del segundo tipo. Expresa que pasaría si se cumpliera una condición imaginaria, hipotética (que es poco probable que se cumpla). En realidad, no tengo un millón de dólares, solamente estoy imaginando qué haría si los tuviera.

If + condición + consecuencia
If + Past + would

Estas oraciones se forman comenzando con IF y agregando la condición, expresada en tiempo pasado. Luego, se agrega lo que ocurriría si se cumple esa condición, expresado con would seguido del verbo.

If I had a calculator, I would do this homework quicker (but I don't have a calculator).
Si tuviera una calculadora, haría esta tarea más rápido (pero no tengo una calculadora).

If you lost your keys, you would have a big problem.
Si perdieras las llaves, tendrías un gran problema.

If I worked less, I would have more free time.
Si trabajara menos, tendría más tiempo libre.

Siempre debe utilizarse el tiempo pasado en la parte de la oración que tiene el if y el verbo modal would en la parte de la oración que contiene la consecuencia. Es incorrecto decir:

If I would work less, I would have more free time.
If I worked less, I would have more free time.

El verbo modal would puede usarse también en su forma contracta 'd.

If I worked less, I'd have more free time.

El verbo modal would puede usarse también en su forma contracta 'd.

If I worked less, I'd have more free time.

La condición tambén puede ser negativa.

If you didn't eat so much, you would be slim.
Si no comieras tanto, estarías en forma.

La consecuencia tambén puede ser negativa.

If you didn't eat so much, you wouldn't be so fat.
Si no comieras tanto, no estarías tan gordo.

También es posible realizar preguntas con las oraciones condicionales.

What would you do if you won the lottery?
¿Qué harías si ganaras la lotería?

Veamos la diferencia con las oraciones condicionales del primer tipo:

Type 1: If we take a bus, it will be cheaper.
Si tomamos un autobús, será más barato.

Type 2: If we took a bus, it would be cheaper.
Si tomáramos un autobús, sería más barato.

En la primera oración se trata de una condición general, se expresa algo que sucederá en el futuro. En cambio, en la segunda oración se trata de una condición irreal, estamos hablando de la posibilidad de tomar un autobús. Es una situación hipotética, que puede suceder o no, pero que solamente estamos imaginando que pasaría.

Exercise 1

Complete los recuadros usando el verbo entre paréntesis en el tiempo y forma que corresponda.
1. If you (stay) , we would play tennis.
2. If we met at three, we (have) plenty of time to play tennis the whole afternoon.
3. If you don't practice, you (fail) again.
4. If the children (come) , we will play football.
5. If the children (come) , we would play football.
6. If you (have) time, call me.
7. If I won the lottery, I (buy) a sports car.
8. If Laura (call) , I will tell you.
9. If we (live) in London, we would eat British food.
10. If Adam comes, please (tell) him to wait
for me.
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Exercise 2

Elija la opción más adecuada para completar cada oración.
If... my boss, he will be very angry.
I ask
I asked
If... enough money, I would travel around Europe.
I had
I have
If... how to cook, I would make you a cake for your birthday.
I knew
you knew
What would you do if... a million dollars?
you had
you have
If I knew the answer,... tell you.
I would
I will
Where... go if you had a car?
will you
would you
If Thomas... so much, he wouldn't be so fat.
didn't eat
wouldn't eat
Richard... the exams if he worked harder.
would pass
passed

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