Ponga los verbos entre paréntesis según corresponda.
1. Hay tres tipos de oraciones subordinadas condicionales. El primero se construye de la siguiente forma:
if (presente), (will + infinitivo) o
(will + infinitivo) if (presente). Este tipo se usa para indicar que algo es posible, probable o real.
If we have time, we will pay you a visit. (Si tenemos tiempo, te haremos una visita.)
a If you (buy) me a beer, I (help) you with your homework.
b If he (be) punctual, we (catch) the 10.45 train.
c If it has stopped raining, I (show) you round town.
d You (arrive) late if you (not hurry) up.
e If it (continue) to snow, we (not be) able to go there today.
2. Dentro del primer tipo también tenemos las siguientes combinaciones:
If you want a kiss, come here. (
if (presente), (imperativo) » Si quieres un beso, ven aquí.)
Don't do it if you're not sure. (
(imperativo) if (presente) » No lo hagas si no estás seguro.)
Metals expand if they're heated. (un hecho universal→
if (presente), (presente) » Los metales se dilatan si se calientan.)
If (=whenever) she comes in, he (always) goes out. (un hábito→
if (presente), (presente) » Si ella entra, él (siempre) sale/Cada vez que ella entra, él (siempre) sale.)
You can stay here if you like. (En vez de
will, se puede usar otro modal. » Puedes quedarte aquí si lo deseas.)
a Metals (contract) if they (be) cooled.
b (not stand) up if you (be) tired.
c If I (go) home late, my parents often (get) angry.
d (sit) down if you (want) to take another tea.
e If it (be) hot, we usually (spend) the day on the beach.
3. En cuanto al segundo tipo, se utiliza para indicar que algo es improbable o irreal, y tiene la estructura siguiente:
if (pasado), (would + infinitivo) o
(would + infinitivo) if (pasado).
If I were you, I would tell the truth. (Yo de ti, diría la verdad.)
If she were here, she would know what to do. (Si ella estuviera aquí, sabría qué hacer.)
I'd buy a big house if I won the lottery. (Me compraría una casa grande si me tocara la lotería.)
a If it (not be) raining cats and dogs, I (go) with you.
b What you (do) if you (see) a burglar at home?
c If he (has) the answer, he (not share) it.
d If Lionel (get) to know this, he (ruin) your marriage.
e You (have) to obey me if your dad (be) here.
4. El tercer tipo se refiere al pasado, y el pasado no lo podemos cambiar. Por eso, se le llama "condicional imposible". Se construye de la siguiente manera:
if (pasado perfecto), (would have + participio de pasado) o
(would have + participio de pasado) if (pasado perfecto).
If she had been here, we would have won the match. (Si hubiese estado aquí, habríamos ganado el partido.)
They could have helped us if they hadn't had the accident. (Habrían podido ayudarnos / Podrían habernos ayudado si no hubiesen tenido el accidente.)
a If you (love) them, you (not abandon) them.
b If Mary (be) in, she (answer) the phone.
c They (not run) out of petrol if they (fill) their car in.
d If he (express) his feelings, he (not lose) her.
e If I (not have) an important meeting, I (take) you out to dinner last night, but I couldn't skip that meeting.
5. Si queremos conectar algo presente o futuro con algo pasado, podemos mezclar los tipos dos y tres, como en los siguientes ejemplos:
If you had drunk that, you would be dead now. (Si te hubieses bebido eso, ahora estarías muerto.)
If my son were ill, I would have noticed. (Si mi hijo estuviera enfermo, me habría dado cuenta.)
a I (be) rich now if I (marry) him then.
b I (take) the dog out to do his business tomorrow morning if you (lend) me a hand this morning.
c If they (need) your help now, they (say) something about it before they left.
d If you (not tell) anybody as I told you, we (not be) in such an embarrassing situation now.
e If he (not study), he (not be) the chairman of this company now.
6. Complete las oraciones condicionales siguientes:
a If there is another strike, we...
b If it weren't sprinkling with rain, we...
c He wouldn't be so unhappy if...
d They would have come if...
e If I were you, I...
f If it hadn't been for you, I...
g I could have helped you if...
h She may forget about it if...
i Your marks are very poor. You'll have to repeat the year unless...
j I'll lend him my car provided that...
k Nobody will know our secret so long as you...
l If you play truant again, you...
m If he hadn't been driving so fast, he...
n If they fired me, I...
o If he hadn't caught me red-handed,...
p If I hadn't entered that disco then,...
q If it continues without raining, our crops...
r They'd give you a bonus if...
s If it weren't for her, they...
t We would have arrived at the meeting in good time if...
u My parents often get cross with me if I...
v Don't let the cat out of the bag again if you...
w He may find out the truth if...
x Life would have been much harder for him if...
y If you need more money,...
z If you say that again,...
7. Vuelva a escribir las oraciones de abajo, empleando if y sin alterar el significado.
Ejemplo:
I'm tired, so I won't dance.
If I weren't tired, I'd dance.
a It's spitting with rain, so I won't go out.
b Tell me what happened or I'll get angry.
c The reason why she was so sad was that her husband had abandoned her.
d Either you keep your mouth shut, or you'll get into trouble.
e She couldn't attend the reception because she was ill in bed.
f I think you should drink less.
g He made a lot of mistakes in his composition, so he failed.
h He lives abroad, so we seldom see each other.
i Visit us some time next week, and we'll take you sightseeing.
j Put this record on and I'll dance with you.
k I can't go there with you because I have a lot of things to do.
l Your stomach aches so terribly because you didn't follow my advice last night.
m We didn't buy the flat, as it was extremely expensive.
n Keep calm. It'll do you good.
o He's so lonely because he's very selfish.
p They used low-quality materials to build the house, so they will have to pull it down now.
q In my opinion, you should sell the house at a cheaper price.
r The neighbours' dog kept on barking the whole night, so I didn't sleep a wink.
s I don't want to go for a swim because it's rather chilly outside.
t I didn't go to school today because I have an awful headache.
u I'm afraid of spiders, so I was very frightened.
v I didn't say hello to you because I didn't see you.
w I don't travel very often. I'm very poor.
x He robbed a bank, so he was arrested.
y I conquered her heart thanks to you.
z I was infatuated with her, which is why I covered up for her.
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Si escribimos primero la oración subordinada condicional, ponemos una coma antes de empezar la principal, pero no, al contrario:
If we begin now, we will finish before dark. (Si empezamos ahora, terminaremos antes de que obscurezca.)
We will finish before dark if we begin now. (Terminaremos antes de que obscurezca si empezamos ahora.)
En vez de
if se pueden usar otras conjunciones condicionales:
If she doesn't help me, I won't be able to go. (Si no me ayuda, no podré ir.)
Unless she helps me, I won't be able to go. (A no ser que me ayude, no podré ir.)
I'll go if he shuts up. (Iré si se calla.)
I'll go provided (that) / providing (that) / as long as / so long as he shuts up. (Iré con tal de que se calle/mientras se calle.)
En preguntas, sólo la oración principal va en interrogativa:
Will he come if it rains? (¿Vendrá si llueve?)
If it rains, will he come? (Si llueve, ¿vendrá?)
Will tiene la forma contracta
'll, y
will not,
won't.
Los imperativos son órdenes, peticiones, etc. Se caracterizan porque no se menciona el sujeto.
Will expand es también posible, pero menos usual:
Metals will expand if they are heated.
Obsérvese que en este tipo de condicional el verbo
to be toma la forma
were para todas las personas, al menos en un estilo más formal.
La forma contracta de
would es
'd. En vez de
would podemos hacer uso de otros modales en condicional como, por ejemplo,
could o
might, pero con matices de significado.
Véase la unidad 7, secciones 11 y 12 para más información sobre el pasado perfecto.
Nótese que en lugar de
would caben otros verbos modales en condicional, pero estos aportan matices diferentes.