25.We go to school by bus______on foot.

　 A.instead　　 B.instead of　　 C.but　　 D.and

24.Children should not______to work in factories in summer holidays.

　 A.allow　　 B.be allowed 　　C.be allowing　 D.allowed

23.He doesn’t seem ______many friends.

　 A.have　　 B.to have　　 C.has　　 D.having

22.Stop polluting to keep the water______.

　 A.cleaning　　 B.cleaned　　 C.to clean　　 D.clean

21.It is ____to work out this problem, you don’t need to ask the teacher for help.

　 A.enough easy　　 B.enough easily　　 C.easy enough　　 D.easily enough

20.My Dad hardly has time for concerts with me now,______.

　 A.has he 　　B.hasn’t he 　　C.doesn’t he　　 D.does he

19.--He went to see the man who was in hospital yesterday.

　 --__________.

　A.So did we　　 B.So we did　　 C.We did so　　 D.Did so we

18.National Day is coming, we’ll have 7 days______.

　 A.on　　 B.off　　 C.up　　 D.down