Conditionals 0, 1, 2 and 3

 Type 0 – Facts

If + Present Simple + Present Simple
or
Present Simple + If + Present Simple

Examples:

If I heat this water, it boils.

This water boils if I heat it.

Type I – Probable situation

If + Present Simple + Future “will” / can + Infinitive
or
Future “will” / can + Infinitive + If + Present Simple

Examples:

If I go to the supermarket, I’ll buy some bread.
I won’t go to the beach if it rains.


Type II – Improbable situations, give advice.


If + Past Simple + Conditional “would” / could + Infinitive
or
Conditional “ Would” + infinitive + if + Past Simple



Examples:

If I were you, I wouldn’t speak to them again.
I wouldn’t speak to them again if I were you.

If we won the lottery, we would travel the world.

We would travel the world if we won the lottery.


Type III – expresses regret; impossible, imaginary situations.


If + Past Perfect + would have + Past participle
or
Would have + past participle + if + past perfect


Examples:

If I had studied harder, I wouldn’t have failed the exam.
I wouldn’t have failed the exam if I had studied harder.


Practice makes perfect:

https://www.bbc.co.uk/learningenglish/english/search?q=conditionals&submit=GO

ht1https://agendaweb.org/verbs/conditional-mixed-exercises.html