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.
0 THE ZERO CONDITIONAL
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.
1 THE FIRST CONDITIONAL
If + subject + present simple, subject + will / be going to
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.
2 THE SECOND CONDITIONAL
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.
3 THE THIRD CONDITIONAL
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:
1) PRESENT RESULT