LONGMAN ENGLISH GRAMMAR PRACTICE

14 Conditional sentences

14.4

14.4A

Study:

Write:

14.4B

Study:

Mixed conditionals; 'unless/if... not', etc.

Mixed tenses in conditional sentences [> LEG 14.3]

We do not always have to stick rigidly to the 'three types of conditional sentences'. There are

occasions when we can use any tenses in /7-clauses, depending on the context:

If I am as clever as you say I am, I would have been rich by now. Type 1 + Type 3

If you knew me better, you wouldn't have said that. Type 2 + Type 3

If I had had your advantages, I'd be better off now. Type 3 + Type 2

Use mixed tenses in these sentences.

1 If I ..НФУк (be) you, I (check) my facts before I wrote that letter.

2 If you (be) so hungry, you (not miss) breakfast.

3 If he (not catch) the 5.30 train, he (not arrive) for another two hours.

4 He (feel) very tired today if he (play) rugby yesterday.

5 If the snake bite (be) poisonous, you (feel) very ill now.

6 If I (be) in your position, I (answer) his letter by now.

'If not' and 'unless' [> LEG 14.20]

1 We can use if... ло/and unless in place of each other when we are saying 'except if.

Unless is 'stronger' than if not and we sometimes use it in 'threats':

If you don't change your mind I won't be able to help you. (= Except if you change ...)

Unless you change your mind, I won't be able to help you. (= Except if you change ...)

2 We cannot use unless in place of if not when if not doesn't mean 'except if:

I'll be surprised if he doesn't win. (if not doesn't mean 'except if)

She'd be better company if she didn't complain so much, (if not doesn't mean 'except if)

3 We often use unless (never if... not) to introduce an afterthought:

I couldn't have got to the meeting - unless, of course, I had caught an earlier train.

Write 1 : Tick the sentences where we could use either if not or unless.

1 I won't do it if you don't help me.

2 Unless he chooses his words more carefully, he'll be in trouble.

3 She'd have more friends if she didn't criticise everyone so much.

4 I'll be surprised if they don't get married one day.

5 She couldn't have stolen the jewels unless she had had inside help.

6 She couldn't have stolen the jewels - unless of course someone had helped her.

7 I'd be very pleased with this car if it didn't break down all the time.

Write 2: Supply if not or unless in these sentences. Note where you could use either.

1 (you/tell) ,Ш<./.. 4Ш... me the whole story, I won't be able to help you.

2 He would be happier and healthier (he/have) so many worries.

3 We couldn't have caught the plane - (we/break) the speed limit getting to the airport.

4 (management and unions/become) more flexible, there'll be a lot more strikes.

5 I'll be there by 7 o'clock (l/get held up) in the traffic.

6 (we/have) more rain soon, the plants will all die.

7 (you/not warn) me, I would have fallen into the same trap as you.