Verbs in conditional sentences

Conditional sentences contain two clauses: a subordinate clause (usually starting with if, when, or unless) and an independent clause. The subordinate clause (sometimes called the if or unless clause) states the condition or cause; the independent clause states the result or effect.

Example sentence: If we walk behind the waterfall, we will get wet. Explanation: The if clause is “If we walk behind the waterfall.” The result clause is “we will get wet.”

Example sentence: Unless Sally finishes her project today, she will not leave for vacation tomorrow. Explanation: The unless clause is “Unless Sally finishes her project today.” The result clause is “she will not leave for vacation tomorrow.”

Verbs in conditional sentences do not express the time of an action in the way that verbs usually do. Rather, the present tenses typically express factual or true conditions, and past tenses typically express speculative or imaginary conditions.

Three kinds of conditional sentences are discussed in this section: factual, predictive, and speculative.

Exercise: Verbs in conditional sentences

subordinate clause A word group containing a subject and a verb that cannot stand alone as a sentence because it begins with a word that marks it as subordinate (such as although, because, who, or that).

independent clause A word group containing a subject and a verb that can or does stand alone as a sentence.