Ciò che è sempre vero: PRESENTE + PRESENTE Ex: If I work late, I got tired.
Ciò che era vero nel passato: PASSATO + PASSATO: Ex: We went home early if it was foggy.
Situazioni reali: PRESENTE + FUTURO Ex: If you keep driving like that, you're going to have an accident.
Ex: If you see Mark, tell him I'll ring him tomorrow.
Situazioni ipotetiche: PASSATO + WOULD (Immaginarie o irreali).
Ex: If I know the answer, I would tell you.
Si può usare SHOULD al posto di WOULD (Alla prima persona).
Ex: If I left home, I think I should be lonely.
Situazioni ipotetiche passate: PAST PERFECT + WOULD HAVE (Irreali o immaginarie).
Ex: If I had known you were coming, I would have met you at the station.
Con i VERBI MODALI: Possibili situazioni nel presente Ex: If you get wet, you should change your clothes immediately.
Situazioni ipotetiche Ex: If I had the money, I could help you.
IF ONLY: If only I hadn't drunk too much, this wouldn't have happened!
EVENTI PASSATI CON RISULTATI NEL PRESENTE: PAST PERFECT + WOULD Ex: If Jim hadn't missed the plane, he would be here by now.