Have to = Moet (informeel)Everyone has to go home by 5 P.M.
We have to study a lot for the test week.
Must = moet (formeel; dwingend / bij wetten, regels, bevelen / wanneer iets logisch is)
Guests must be quiet after 11 p.m.
You must stop at a stop sign.
He must be tired after that long run.
Should = zou moeten (advies)
You really should brush your teeth before you go to bed.
Don't have to / Doesn't have to = hoeft niet
You don't have to do any assignments about the book that you are reading