If-Clauses in English Grammar: Zero Conditional

Zero conditional is used to express things that always happen providing a certain condition (expressed in the if-clause) is met.

Construction

Rule 1: To form the zero conditional, we use the present tense in both the if-clause and the main clause.

Note: We can reverse the order of the clauses with no change in meaning. But, if the if-clause comes first, it should be separated by a comma. If the main clause is first, we don't need a comma.

Usage

Rule 2: We use zero conditional if-clauses to express general facts and truths.

Rule 3: We use zero conditional if-clauses to talk about habits.

Rule 4: We use zero conditional if-clauses to talk about rules.

If Vs. When

Rule 5: Zero conditional sentences express almost the same meaning as time clauses with when (emphasizes the certainty of an action) and whenever (i.e., at any time or every time when).

Comparison with Other Conditionals

Zero Conditional vs. First Conditional

Rule 6: The zero conditional talks about general truth and facts, whereas the first conditional describes a particular situation.

Zero Conditional vs. Second Conditional

Rule 7: While zero conditional refers to general truths, the second conditional talks about unlikely or hypothetical situations and their probable result.

Zero Conditional vs. Third Conditional

Rule 8: In contrast to the general truth, instructions, and scientific facts we share using zero conditional, the third conditional talks exclusively about hypothetical situations in the past.