Fill in the blanks.
Use:should/shouldnt/must/neednt/have to.
Shall I buy some butter?-No,you ... . We ve got some.
What ... I do to pass the chemistry exam?-You ... work hard and spend more time doing your homework.
Excuse me , I ... ...get to Trafalgar Square. ... I take a bus?-Yes.You ... take buss № 62.