Assunto: If clause (Third Conditional)A third conditional sã...

  Assunto: If clause (Third Conditional)
A third conditional são sentenças condicionais usadas para falar do passado. Ela faz referência a algo que não ocorreu no passado e, portanto, pode expressar arrependimento. Todas as orações condicionais em inglês (if clauses) são acompanhadas pelo termo if (se).
Exemplo: 

If we had saved some money, we would have bought a new phone. 
(Se nós tivéssemos economizado dinheiro, nós teríamos comprado um telefone novo)

Formação

A third conditional é formada pela if clause e a main clause. A if clause é composta por verbos no past perfect, já a main clause envolve diversos verbos sendo que os mais utilizados são: would have, could have e might have.
Após a main clause, os verbos que surgem aparecem no past participle.

If + past perfect + would have, could have, might have + past participle

Exemplos:

If he had come on Monday, I would have seen him. 
(Se ele tivesse vindo na segunda, o teria visto)

If she had worked more, she could have saved more money. 
(Se ela tivesse trabalhando mais, poderia ter economizado mais dinheiro)

If we had studied harder, we might have passed the test. 
(Se nós tivéssemos estudado mais duro, poderíamos ter passado na prova)

Obs: Nas sentenças negativas, os verbos modais podem aparecer com as contrações:

Would: would not – wouldn’t
Could: could not – couldn’t
Might: might not – mightn’t

Exercises

01. Turning the third frame of the strip into the third conditional, we would have:
a) “And if anything had been, by Golly, I would have been ready for it!”
b) “And if anything happened, by Golly, I’d be ready for it!”
c) “And if anything did, by Golly, I would be ready for it!”
d) “And if anything had happened, by Golly, I’d be ready for it!”
e) “And had anything happened, by Golly, I’d have been ready for it!”
02. The underlined sentence ‘If you knew what was going on above your head, you probably wouldn’t sleep at night,’ in the third conditional would be:

a) Had you known what was going on above your head, you probably wouldn’t have slept at night.
b) If you hadn’t known what was going on above your head, you probably wouldn’t sleep at night.
c) If you had known what was going on above your head, you probably would have slept at night.
d) Unless you hadn’t known what was going on above your head, you probably would sleep at night. (Correta)
e) Unless you had known knew what was going on above your head, you probably wouldn’t have slept at night.
 

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