Question

Заполните пропуск:
If I were you, I … people about this problem.

will inform

informed

inform

would inform

Answer 1

If I were you, I would inform people about this problem.

Answer 2

would inform.
Первая часть (с If ) показывает нам то, что тут использован II Conditional:
(If + Ps.Simple) + ( would + V1 ( result )).