if. Problems often arise in deciding whether if is introducing a subjunctive clause ('If I were ...') or an indicative one ('If I was ...'). The distinction is straightforward. When if introduces a notion that is hypothetical or improbable or clearly untrue, the verb should be in the subjunctive: 'If I were king ...'; 'If he were in your shoes ...'. But when the if is introducing a thought that is true or could well be true, the mood should be indicative: 'If I was happy then, I certainly am not now'. One small hint: if the sentence contains would or wouldn't, the mood is subjunctive, as in 'If I were you, I wouldn't take the job'.