Zero and First Conditional Review

Compare facts with real future possibilities.

Examples

• If you heat ice, it melts.
• If it rains, I'll stay home.

Key rules

• Zero conditional: If + present simple, present simple (facts)
• First conditional: If + present simple, will + base verb (real future)
• Never use will in the if-clause
• You can swap the clauses with no comma (I'll stay if it rains)

Common mistakes

• If it will rain, I'll stay → If it rains, I'll stay
• If you will heat ice → If you heat ice