The past tense is sometimes used in English to refer to an 'unreal' situation. So, although the tense is the past, we are usually talking about the present, e.g. in a Type 2 conditional sentence:
If an elephant and a mouse fell in love, they would have many problems.
Although fell is in the past tense, we are talking about a hypothetical situation that might exist now or at any time, but we are not referring to the past. We call this use the unreal past.
Other situations where this occurs are:
The following expressions can be used to introduce hypothetical situations:
- supposing, if only, what if. They are followed by a past tense to indicate that the condition they introduce is unreal:
These expressions can also introduce hypothetical situations in the past and then they are followed by the past perfect.
The verb to wish is followed by an 'unreal' past tense when we want to talk about situations in the present that we are not happy about but cannot change:
NOTE: When we want to talk about situations we are not happy about and where we wantsomeone else to change them, we use to wish followed by would + infinitive:
These two expressions are also followed by an unreal past. The verb is in the past tense, but the situation is in the present.
When we want to talk about a course of action we would prefer someone else to take, we use I'd rather + past tense:
NOTE: the stress can be important in these sentences, to show what our preference is:
Similarly, when we want to say that now is a suitable moment to do something, either for ourselves or for someone else, we use it's time + past tense:
It is possible for the two parts of a conditional sentence to refer to different times, and the resulting sentence is a "mixed conditional" sentence. There are two types of mixed conditional sentence:
The tense in the 'if' clause is the past perfect, and the tense in the main clause is the present conditional:
IF' CLAUSE | MAIN CLAUSE |
If + past perfectIf I had worked harder at school | Present conditionalI would have a better job now. |
In these sentences, the time is past in the 'if' clause, and present in the main clause. They refer to an unreal past condition and its probable result in the present. They express a situation which is contrary to reality both in the past and in the present:
The tense in the If-clause is the simple past, and the tense in the main clause is the perfect conditional:
IF' CLAUSE | MAIN CLAUSE |
If + simple pastIf I wasn't afraid of spiders | Perfect conditionalI would have picked it up. |
In these sentences the time in the If-clause is now or always, and the time in the main clause is before now. They refer to an unreal present situation and its probable (but unreal) past result:
a. If she wasn't afraid of flying she wouldn't have travelled by boat.
b. I'd have been able to translate the letter if my Italian was better.
c. If I was a good cook, I'd have invited them to lunch.
d. If the elephant wasn't in love with the mouse, she'd have trodden on him by now.
Unless means the same as if...not. Like if, it is followed by a present tense, a past tense or a past perfect (never by 'would'). It is used instead of if + not in conditional sentences of all types:
Type 1: (Unless + present) |
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Type 2: (Unless + past) |
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Type 3: (Unless + past perfect) |
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In a Type 3 conditional sentence, the tense in the 'if' clause is the past perfect, and the tense in the main clause is the perfect conditional:
IF' CLAUSE | MAIN CLAUSE |
If + past perfectIf it had rained | Perfect conditionalyou would have got wet |
The perfect conditional of any verb is composed of two elements: would + the perfect infinitive of the main verb (=have + past participle):
Subject | would | perfect infinitive |
He They | would would | have gone... have stayed... |
Affirmative | ||
I | would | have believed ... |
Negative | ||
She | wouldn't | have given... |
Interrogative | ||
Would | you | have left...? |
Interrogative negative | ||
Wouldn't | he | have been...? |
Affirmative | Negative | Interrogative |
I would have gone | I wouldn't have gone | Would I have gone? |
You would have gone | You wouldn't have gone | Would you have gone? |
He would have gone | She wouldn't have gone | Would it have gone? |
We would have gone | We wouldn't have gone | Would we have gone? |
You would have gone | You wouldn't have gone | Would you have gone? |
They would have gone | They wouldn't have gone | Would they have gone? |
In these sentences, the time is past, and the situation is contrary to reality. The facts they are based on are the opposite of what is expressed.
Type 3 conditional sentences, are truly hypothetical or unreal, because it is now too late for the condition or its result to exist. There is always an unspoken "but..." phrase:
NOTE: Both would and had can be contracted to 'd, ++which can be confusing. Remember that you NEVER use would in the IF-clause, so in the example above, "If I'd known" must be"If I had known", and "I'd have baked" must be "I would have baked.."
a. If I'd known you were in hospital, I would have visited you.
b. I would have bought you a present if I'd known it was your birthday.
c. If they'd had a better goalkeeper they wouldn't have lost the game.
d. If you had told me you were on the Internet, I'd have sent you an e-mail.
e. Would you have bought an elephant if you'd known how much they eat?
This tense is composed of two elements: the perfect condtional of the verb 'to be' (would have been) + the present participle (base+ing).
Subject | would have been | base+ing |
I We | would have been would have been | sitting swimming |
Affirmative | ||
I | would have been | studying. |
Negative | ||
You | wouldn't have been | living. |
Interrogative | ||
Would | we have been | travelling? |
Interrogative negative | ||
Wouldn't | it have been | working? |
Affirmative | Negative |
I would have been working | I wouldn't have been working |
You would have been working | You wouldn't have been working. |
He would have been working | She wouldn't have been working |
We would have been working | We wouldn't have been working |
You would have been working | You wouldn't have been working |
They would have been working | They wouldn't have been working |
Interrogative | Interrogative negative |
Would I have been working? | Wouldn't I have been working? |
Would you have been working? | Wouldn't you have been working? |
Would he have been working? | Wouldn't she have been working? |
Would we have been working? | Wouldn't we have been working? |
Would you have been working? | Wouldn't you have been working? |
Would they have been working? | Wouldn't they have been working? |
This tense can be used in Type 3 conditional sentences. It refers to the unfulfilled result of the action in the if-clause, and expresses this result as an unfinished or continuous action. Again, there is always an unspoken "but.." phrase: