If Clauses – Conditional sentences

As frases condicionais (If Clauses) expressam a dependência ou condição de um fato ou resultado. Essas condições ou fatos podem ser presentes, passados ou futuros. Uma frase condicional é formada por duas partes: main clause e conditional clause. Veja:

       conditional clause                  main clause 

                       If      it rains,        |      we’re going to stay in the house.

As diferenças entre os tempos verbais são importantes para determinar se a situação é possível, provável ou apenas imaginária. Abaixo temos os tipos de frases condicionais:

 The first, second and third conditionals

 The first conditional

A estrutura desse tipo é:

if + present simple tense + modal verb with future reference (e.g. will/ shall/ may).

In the first conditional, a speaker predicts a likely result:

• If Sally comes too, there’ll be five of us.
• We won’t have enough time if we want to do some shopping too.
• If I study, I’ll pass the exams.

The second conditional

A estrutura desse tipo é:

if + simple past tense + modal verb with future-in-the-past reference (e.g. would/could/might).

In the second conditional, a speaker responds to a possible or hypothetical situation by indicating a possible outcome.

• If I knew what you wanted, maybe I could help you.
• I would do a computer course if I had the time.
• If I studied, I would pass the exams.

The third conditional

A estrutura desse tipo é:

if + past perfect tense + modal verb with future-in-the-past reference (e.g. would/could/might) + have + -ed participle.

In the third conditional, the is talking about a past event which did not happen, and therefore things are different from how they might have been:

• If I had seen you walking, I could have offered you a ride.
• John would have been furious if he had heard her say that.
• If I had studied, I would have passed the exams.

Além dessas três, há outros tipos de estruturas com IF. Venha aprender mais no Yázigi Vila Mariana/ Metrô Santa Cruz. Matrículas abertas para 2013! Tel: (11) 5579-4930.

Referência:
Cambridge Grammar of English. Ronald Carter and Michael McCarthy.
Cambridge University Press