Which sentence uses the subjunctive form correctly?

• A. If caffeine was banned on college campuses, more assignments would be turned in late.
• B. If caffeine were banned on college campuses, more assignments would be turned in late.
• C. If caffeine is banned on college campuses, more assignments would be turned in late.
• D. If caffeine are banned on college campuses, more assignments would be turned in late.

Answer: (B)

Subjunctive mood in hypothetical conditionals uses were in the if-clause to show the situation isn’t real, with would in the main clause to express the consequence. Here, the sentence that uses were in the if-clause correctly reflects a nonreal condition: If caffeine were banned on college campuses, more assignments would be turned in late. The would be turned in late part describes the expected outcome if that imaginary ban occurred, with a passive construction that fits the hypothetical scenario.

The other forms treat the condition as real or as a factual possibility, which isn’t how a purely hypothetical scenario is framed in standard English. For example, using is or are signals real possibility, and using was signals a past reality rather than a counterfactual. Note that in informal speech, some people say was, but the standard, preferred form for a hypothetical condition is were.