10．It's very easy for me to find his home.

　 I have_________ trouble_________ his home.

9．They are going to the concert, they aren't going to go swimming.

　 They are going to the concert _________ _________going swimming.

8．If she doesn't study hard, she will fail the exam.

　 _________she _________ hard, she will fail the exam,

7．Listening to tapes improves my listening skill.

　 I improve my listening skill_________ _________to tapes.

6．Miss Eric doesn't agree with me.

　 Miss Eric_________ _________me.

5．We don't know how we should use commas.

　 We don't know_________ _________use commas.

4．We should allow teenagers to choose their own clothes

　 Teenagers should _________ _________ to choose their own clothes.