Sentence, Clause, Phrase - The Zero, First, Second and Third Conditionals

The Zero Conditional

To state general truths or scientific facts

If you cool water to 0°C, it changes into ice. OR Water changes into ice if it is cooled to 0°C.

[Note: You can use ‘when’ in the place of ‘if’ in such sentences.]

The First Conditional

To indicate something that may happen in the present or in the future

If you talk to my brother, he will tell you exactly where the jewels are hidden. If I see you at the stadium, I will give you a call.

The Second Conditional

To indicate an unreal situation in the present or in the future; Often used for expressing a wish

If I were you, I would approach this issue in a different way. If I had more time, I would join some theatre group.

The Third Conditional

To indicate something that did not happen in the past

If he had been more observant, he would have solved the case. If they had played as a team, they would have won the final.

[Note: In this case, you can also use ‘could’ or ‘should’ in the place of ‘would’.]