单项选择题
A.have to B.don‘t have to C.must D.mustn‘t
People wandering in the fairground or park area（）wear a...
单项选择题People wandering in the fairground or park area（）wear a uniform.
A.must B.mustn‘t C.have to D.don‘t have to
Not until most of the people had left the airport（）his ...
单项选择题Not until most of the people had left the airport（）his sister was there.
A.that he saw B.had he seen C.did he see D.that he had seen
Not always（）they want (to)A.people can do whatB.can peo...
单项选择题Not always（）they want (to)
A.people can do what B.can people do what C.people can not do what D.can‘t people do what
