Do you know how to use third and mixed conditionals?

Third conditionals and mixed conditionals

Conditionals are sentences with two clauses – an if clause and a main clause – that are closely related. Conditional sentences are often divided into different types.

Third conditional

Third conditional sentences describe the past. They describe something that didn't happen.

  • If I'd studied harder at school, I would have gone to university.

He didn't study very hard and he didn't go to university.

  • We wouldn't have got lost if you hadn't given me the wrong directions.

She wasn't given the correct directions and she didn't find her way.

  • She might have finished the exam if she'd had more time.

She didn't finish the exam and she didn't have more time.

In third conditional sentences, the structure is usually if + past perfect and would + perfect infinitive (e.g. have done). It's not important which clause comes first.

Notice that other modal verbs can be used instead of would (e.g. could, might, may)

Mixed conditionals

In mixed conditional sentences the time in the if clause is not the same as the time in the main clause. There can be various combinations.

  • If he'd gone to university, he might have a better job.

He didn't go to university (past)
He doesn't have a very good job. (present)
This sentence shows the present consequences of a past action.

  • If I'd won the competition, I'd be going to Florida next week.

She didn't win the competition (past)
She isn't going to Florida (future)
This sentence shows the future consequences of a past action.



Language level

Upper intermediate: B2


Hi again jiyi,

Sentence 1 is indeed a mixed conditional (with third conditional in the first part and second conditional in the second part) and it is grammatical. 'had kissed' refers to an action that could have happened in the past (but did not) and 'would have to apologise' refers to an imaginary action in the present or future (that also isn't happening).

Sentence 2 is a second conditional construction, with a verb in the past simple ('kissed') in the 'if'-clause and 'would' + base form in the other clause. Your explanation correctly explains the idea of the sentence.

All the best,
The LearnEnglish Team

Dear teachers,
I,ve read a few of the comments here but I am having difficulty to understand some of the examples given:

1. 'If I had kissed the girl, I would have to apologize to her.'
I had a debate with my friend last night because she thought that this is a 3rd conditional (because of the 'would have') , but I think that this is more like a mixed conditionals, am I right?

2. You said that: 'If I kissed the girl, I would have to apologize to her' is wrong, because it combines real and unreal situation. I don't really get it. Can you please explain this with more details(which one is real and unreal) ?

I thought that this was true because it follows a 2nd conditional ( and I think the questioner was thinking about present hypothetical situation) ?
But you gave another example instead:

'If I kissed the girl, I will have to apologize to her.'
which obviously has different meaning( not hypothetical).

Please help me to understand this. I am confuse. Thank you very much :)

Hi jiyi,

I'm afraid I can't find the examples you are speaking of on this page. In sentence 1, the second verb would need to be 'would have had' for it to be a full third conditional structure. Sentence 2 looks correct to me.

I think what might be confusing you is the form 'to have to', which indicates obligation. It can be confusing, because 'have' is also part of the 'would have + past participle' form that is used in the third conditional. If you changed the second part to just 'apologise' (instead of 'have to apologise'), then you'd get:

1st conditional: If I kiss her, I will apologise
2nd conditional: If I kissed her, I would apologise
3rd conditional: If I had kissed her, I would have apologised

I hope that clears it up for you.

All the best,
The LearnEnglish Team

Could you please explain" wouldn't+ verb"? For example:
I wouldn't leave the office until I had checked that all the doors were locked.
My question is: shouldn´t we use "didn't leave" instead of "wouldn´t leave" or is it correct as it is.
Thank you.

Hello Ahmed Imam,

What is correct here depends on the situation and what the speaker means. If this sentence is about a specific past action, then you are right, 'didn't leave' is the best form. 'would' can be used to speak about past habitual actions, however, so it is actually possible to use it here if that's what the speaker means.

All the best,
The LearnEnglish Team

Hello everyone, first I would like to thank you all for the extraordinary efforts you are doing. Could you kindly correct me for the following sentences?

1)) Supposed we are in summer and I would say: " She would go skiing if it snowed tomorrow" ; I imagine it had a chance to snow tomorrow, even in hot summer.

2)) In the same day which it supposed to snow, but did not, I would say: "She would go skiing now if it had snowed."

3)) The day after , I would say: "She would have gone skiing if it had snowed yesterday."

Am I using "if" correctly?

Thank you in advance and greetings.

Hello Hopefinder,

All of those sentences are correct. Well done!



The LearnEnglish Team

Thanks Peter, I really appreciate your reply.

Hi everyone @TheLearnEnglishTeam. I thought I knew all the rules related to conditional sentences until I came across the following sentence uttered by a native speaker (a very famous native speaker, by the way). This is the sentence: "If we didn’t build the public infrastructure in the early 20th century to support mass electrification, only the wealthy would have had heat and running water". My question is: shouldn´t he have started the "if" clause using "If we hadn´t built". This would make more sense to me. Am I wrong? Thank you for your kind reply. Cheers!

Hi MariaMafalda,

Yes, 'if we hadn't built' is the most correct form here. As you can see, native speakers do make mistakes, particularly when speaking spontaneously, in which people often change structures in mid-sentence.

Best wishes,
The LearnEnglish Team