The zero conditional Form:

Transcription

1 CONDITIONAL SENTENCES Conditional sentences have two clauses: the conditional clause (starting with if) and the main clause. There are four types of conditionals (zero, first, second and third) according to the degree of probability that they express and whether they are talking about the future, present or past. The zero conditional Form: If / when + subject + present simple subject + present simple / imperative or Subject + present simple / imperative if / when + subject + present simple as the order of the two clauses is flexible, but you must remember to use a comma after the conditional clause when it comes first. Use: To refer to an event or situation that is always true. e.g : Life is more difficult if you are poor. To give commands e.g. : If you find a bargain, buy it.

2 The first conditional Form: If + subject + present simple subject + will / modal + infinitive Or subject + will / modal + infinitive If + subject + present simple e.g. : If you go to the party, you will / may enjoy it. Use: We use the first conditional: To talk about possible or probable future events. e.g. : If I finish the project soon, I will go to the cinema with you. To make promises and give warning e.g. : If you keep behaving like this, I ll punish you. (warning) I ll let you go to the party if you pass the exam. (promise) You can use the imperative too. e.g. : Look for (imperative) a summer job if you want to buy a motorbike.

3 The second conditional Form: If + subject + past simple or Subject + simple conditional / modal Subject + simple conditional / modal If + subject + past simple e.g. : If we had enough money, we would / could stay in an expensive hotel. or We would / could stay in an expensive hotel if we had enough money. Be careful! We usually use were, not was, in the first and third persons in written and formal spoken English, although we can still use was in informal and spoken English. e.g. : If I were you, I wouldn t buy it. If he were here, I d be happy. Use : We use the second conditional to talk about hypothetical (imaginary and improbable) present and future situations. e.g. : If I won the lottery, I would / could buy a house in the Caribbean. (I didn t win the lottery so I won t buy a house in the Caribbean.) We can use the imperative in the main clause too. e.g. : If you saw Susan, tell her I want to talk to her.

4 The third conditional Form : If + subject + past perfect Subject + would / could + have + past participle or Subject + would / could + have + past participle If + subject + past perfect e.g. : If they had had enough money, they would / could have gone to the concert. or They would / could have gone to the concert if they had had enough money. Use : We use the third conditional to talk about hypothetical past events (events which did not happen). e.g. : If Peter had studied, he would /could have passed the exams. (Peter didn t study, so he didn t pass the exam.) We wouldn t have missed the train if we had got up earlier. (We didn t get up earlier, so we missed the train.)

5 MIXED CONDITIONALS Use : Mixed conditional sentences combine two different types of conditional forms. They are used when the time reference in the if clause is different from the time reference in the main clause. They are usually a combination of second and third conditionals, but other combinations are possible. e.g. : If Peter hadn t broken into a house, he wouldn t be in prisson now. (third conditional if clause + second conditional main clause) If John weren t so shy, he would have asked Susan out. (second conditional if clause + third conditional main clause)

6 CONDITIONAL CONJUNCTIONS We can use different words and phrases to replace if in a conditional clause. When the conditional clause appears first in a sentence, we use a comma to separate it from the main clause. e.g. : Providing that you can catch fish, you ll survive in a desert island. Even if (aún cuando) We use even if to emphasize the condition in the present / future or past. e.g. : Even if I were a millionaire, I wouldn t give them any money. (present / future) Even if I d been a millionaire, I wouldn t have given them any money. (past) Even if you tell the truth now, nobody will believe you. (present / future) As long as / providing (that) / provided (that) (siempre que, con tal que) These phrases mean only if. We often use them with the first and second conditionals. e.g. : As long as you pay me back by next Friday, I ll lend you the money. We ll get the tickets providing that you agree to drive us to the concert.

7 Unless (a menos que) We can express negative conditions with unless, which means if not. It always refers to the conditional clause and not the main clause in the sentence. e.g. : That new clothes shop will have to close unless it gets more customers. (= That new clothes shop will have to close if it doesn t get more customers.) You ll never understand English unless you study this grammar thoroughly. (= You ll never understand English if you don t study this grammar thoroughly.)