|Structure of the zero conditional|
|If/when you heat water to 100 degrees, it boils.||If/when you don't heat water to 100 degrees, it doesn't boil.||What happens if/when you heat water to 100 degrees?|
|The zero conditional - common mistakes|
|Common mistakes||Correct version||Why?|
If/when people eat too much, they get fat.
Water boils when it reaches 100°C.
We use the present simple in both clauses of the zero conditional. We are saying that the condition can be true at any time (it is a fact).
If means the same as when in a zero conditional sentence. We can also use whenever.