top of page
  • Writer's pictureTC


Updated: Jan 27

- we can identify six types of conditional clauses: zero, first, second, third + two mixed ones

For the start, let’s repeat what the difference is between 'sentence' and 'clause'.

I will pick you up if you call me.

All the underlined words form a sentence. This sentence consists of two clauses.

The first clause is the main clause.

The second clause is the subordinate clause, in this case marked with a conditional conjunction ‘if’.

If the main clause is written first, a comma is not used to separate these two clauses. However, if the subordinate clause is first, there must be a comma.

If you call me, I will pick you up.


If/when + subject + present simple, subject + present simple

  • when = if

  • common states or events, facts, general truths, laws, and rules

  • the situation is real and possible

  • also used to give instructions with the imperative in the main clause*

If/When we heat ice, it melts.

If/When I need money, I go to the bank.

If/When the sun shines, it is warm.

I don’t eat if/when I am not hungry.

*If your dad comes home, tell him to call me immediately.

*Look at me if I talk to you.


If + subject + present simple, subject + will / be going to

  • if

  • possible future states or events

  • future situations which are real or possible

If I have a chance, I will go on holiday.

If she gives up, she won't get a new job.

If it doesn’t snow, we are not going to the Giant Mountains.

  • Unless + positive verb form in present simple can be used instead of ‘if not’

Mary won’t come unless you invite her personally.

You won’t pass the exam unless you study hard.


If + subject + past simple/continuous, subject + would/could/might/should

  • unlikely or imaginary (hypothetical) states or events in the present or future

  • we use I/ he / she / it were (subjunctive) instead of ‘was’ in formal contexts

  • to give advice we often use: If I were you, I’d …

If I didn't cook, we would be hungry.

If I were you, I would go on holiday.

If Marcel had more money, he would travel around the world.

I would buy a yacht if I were a billionaire.


If + subject + past perfect, subject + would/could/might/should + have + past participle

  • imaginary (unreal) states or events in the past

If I had studied better, I would have enrolled at a better university.

Paula could have stopped by if she had wanted to.

Mark would have helped you if you had asked him.

When you start with the if clause, a comma follows. If it is the other way round and the main clause is at the beginning, there is no comma.

Instead of if, we can also use: if so, given, otherwise and provided (that) /providing that

We don’t use so, which is used in Czech:

Kdybych byla tebou, tak bych mu nevolala. If I were you, so I wouldn’t call him.


Sometimes you can come across sentences that are conditional but look a bit different and do not fit the preceding four types. They might be mixed. We differentiate two types of mixed conditionals: