If Clauses

Primer Condicional:

Se emplea cuando una situación es real o posible.

Ejemplo: If it rains today, I'll stay at home (Si llueve hoy, me quedaré en casa). 

Estructura:

• If it rains today, I'll stay at home.
  Si llueve hoy, me quedaré en casa.
• If he is busy now, I will come back tomorrow.
  Si está ocupado ahora, regresaré mañana.
• If I have time, I'll visit my parents this afternoon.
  Si tengo tiempo, visitaré a mis padres esta tarde.
• If it is warm tomorrow, we'll go to the beach.
  Si está caluroso mañana, iremos a la playa.
• If it is cold, you must wear warm clothes.
  Si está frío, debes usar ropa abrigada.
• If he doesn't do his homework, he can not go to the party.
  Si él no hace su tarea, no puede ir a la fiesta.
• If she doesn't call you, you can call her.
  Si ella no te llama, tú puedes llamarla.
• If you work hard, you may become a millonaire someday.
  Si trabajas duro, puede que te conviertas en un millonario algún día.
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• If you spend more than you earn, you'll become a poor man.
  Si gastas más de lo que ganas, te convertirás en un hombre pobre.
• If they don't invite you, you must not go.
  Si ellos no te invitan, no debes ir.
• If we don't hurry, we'll miss our bus.
  Si no nos apuramos, perderemos nuestro autobus.
• If you pay now, you'll get a discount.
  Si pagas ahora, obtendrás un descuento.
• If they don't want to go out, they can stay home.
  Si no quieren salir, se pueden quedar en casa.
• If you drink too much, you'll get drunk.
  Si bebes demasiado, te emborracharás.
• If you feel sick, you must stay in bed.
  Si te sientes enfermo, debes quedarte en cama.
• If they don't come here, we'll have to go there.
  Si ellos no vienen aquí, tendremos que ir allí.

Segundo Condicional:

Refiere a una situación hipotética y se forma según la estructura if + pasado simple + condicional simple. 

• If I won the lottery, I would travel around the world.
  Si ganara la lotería, viajaría por todo el mundo.
• If I were in Brazil, I would go to Rio de Janeiro.
  Si yo estuviese en Brasil, iría a Río de Janeiro.
• If I were you, I would buy that car.
  Si yo fuese tú, compraría ese auto.
• If he were in my place, he wouldn't do this.
  Si él estuviese en mi lugar, no haría esto.
• If I had more money, I would buy a nice apartment.
  Si yo tuviese más dinero, me compraría un lindo apartamento.
• If she had more time, she would travel more often.
  Si ella tuviera más tiempo, viajaría más a menudo.
• If it were not raining, we could go out.
  Si no estuviese lloviendo, podríamos salir.
• If we didn't have to work today, we could have a picnic.
  Si no tuviésemos que trabajar hoy, podríamos tener un picnic.
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• If they won the lottery, they wouldn't work any more.
  Si ellos ganaran la lotería, no trabajarían más.
• If I saw her, I would ask her out.
  Si la viera, la invitaría a salir.
• If you went to Brazil, you wouldn't want to come back.
  Si fueras a Brazil, no querrías regresar.
• If they spoke Spanish, we would understand them.
  Si ellos hablasen español, los entenderíamos.
• If he didn't live by the river, he couldn't go fishing.
  Si el no viviera cerca del río, no podría ir a pescar.
• If I didn't want to go, I would tell you.
  Si no quisiera ir, te lo diría.
• If they worked for that company, they might have better salaries.
  Si ellos trabajaran para esa compañía, podrían tener mejores sueldos.
• If she wrote a book, it would be a best-seller.
  Si ella escribiese un libro, sería un best-seller.

Tercer Condicional:

Refiere a una situación hipotética del pasado y se forma según la estructura : if + pasado perfecto + condicional perfecto. 

• If I had won the lottery, I would have traveled around the world.
  Si yo hubiera ganado la lotería, habría viajado por todo el mundo.
• If I had seen him, I would have told him about you.
  Si lo hubiese visto, le habría contado acerca de ti.
• If I had known the answer, I would have raised my hand.
  Si hubiese sabido la respuesta, habría levantado mi mano.
• If she had come on Saturday, I would have seen her.
  Si ella hubiese venido el sábado, la habría visto.
• If they had left earlier, they would have arrived on time.
  Si ellos hubiesen salido más temprano, habrían llegado a tiempo.
• If we had studied harder, we might have passed the test.
  Si hubiésemos estudiado más duro, podríamos haber aprobado la prueba.
• If you had gone to Brazil, you would have had lots of fun.
  Si tu hubieses ido a Brasil, habrías tenido mucha diversión.
• If I hadn't been so busy, I could have helped you.
  Si no hubiese estado tan ocupado, te podría haber ayudado.
•  
• If you had phoned me, I would have known you were here.
  Si tu me hubieses telefoneado, habría sabido que estabas aquí.
• If they had invited us, we would have accepted at once.
  Si ellos nos hubiesen invitado, habríamos aceptado de inmediato.
• If she had explained me the problem, I would have understood it.
  Si ella me hubiese explicado el problema, lo habría entendido.
• If I hadn't forgotten his number, I would have phoned him.
  Si no hubiese olvidado su número, lo habría llamado.
• If it hadn't rained, we would have gone fishing.
  Si no hubiese llovido, habríamos ido a pescar.
• If my sister had been here, she would have enjoyed this.
  Si mi hermana hubiese estado aquí, habría disfrutado esto.
• If they hadn't drunk so much last night, they wouldn't have felt sick today.
  Si no hubiesen tomado tanto anoche, no se habrían sentido enfermos hoy.
• If he had worked more, he could have saved more money.
  Si él hubiese trabajado más, podría haver ahorrado más dinero