“If I were you, I would [start exercising].”

How often have you heard someone say that statement?  Our teachers have taught us that singular subjects are followed by singular verbs. Check out my post on Subject-verb Agreement.

Back to the above statement. Why do we use the verb “were” instead of “was“? The answer is, it has something to do with “mood” of the verbs used. There are three types of mood:

  • indicative: “You have to come.”
  • imperative: “Come here!”
  • subjunctive: “If I were taller, I would be able to reach it.”

(a) Present subjunctive

In the present subjunctive, use “were” for people.

Example:

  • If I were rich, I would be a philanthropist.

→ I am not rich (this is a factual statement).

(b) Past subjunctive

In the past subjunctive mood, use “had” in all cases.

Examples:

  • If the police had arrived sooner, the robber wouldn’t have escaped.

→ The police arrived late (this is a factual statement).

Remember this:
Subjunctive mood is the use of “mood” verbs to express conditions, hypotheses, and wishes.