Have to and Must
have / You / to / wear / when / gloves / mountain-biking / are / you
You have to wear gloves when you are mountain-biking
mustn't / ride off / You / it / because / dangerous / is
You mustn’t ride off the path because it is dangerous
/ a / stop / have / when / red / see / You / you / flag
You have to stop when you see a red flag.