28.I don’t like the pop singer’s songs.In fact.I’ve trouble________the words of his songs.

A.understand B.to understand

C.understood D.understanding

解析：选D。have trouble(in) doing sth.表示“做某事有困难”。

29.Drivers are warned that it is dangerous to talk on the phone while________.

A.drive B.driving

C.drove D.to drive

解析：选B。当while引导的时间状语从句与主句主语一致且谓语含有be时，可省略从句的主语和be，while driving=while they are driving。

30.—Have you ever been to Shanghai Expo Garden?

—No.It is the first time that I________to China.

A.come B.have come

C.am coming D.came

解析：选B。在句型it is the first/second...time that...中，that后的从句一般用现在完成时。

31.David said that it was because of his strong interest in literature________he chose the course.

A.that B.what

C.why D.how

解析：选A。这是一个it强调句式，对原因状语进行的强调。原句为：David said that he chose the course because of his strong interest in literature.。

32.—Did the boys break the window________?

—No.They did it when they were playing football.

A.by accident B.on purpose

C.at dusk D.as usual

解析：选B。考查短语辨析。由答语可知问话人主要是问“是否故意打破窗户”，故选on purpose(故意地)。by accident偶然;at dusk在黄昏时;as usual像往常一样。

33.As we all know，parents are concerned________their children’s study，because it is concerned________their future.

A.about;with B.about;for

C.for;about D.with;about

解析：选A。be concerned about“对……关心”;be concerned with“涉及到，牵扯到，与……有关”。句意为“众所周知，父母对孩子的学习非常关心，因为这关系到孩子们的将来。”

34.I have some trouble________physics.I would be grateful________you if you could give me some advice on it.

A.with;for B.in;to

C.in;with D.with;to

解析：选D。have trouble with sth.“学……困难”;be grateful to sb.(for sth.)“因……而感激某人”。

35.—So you didn’t say “Hi” to your partner when you saw her?

—Well，I stopped and smiled at her，but she________me and walked on with her head high.

A.refused B.failed

C.missed D.ignored

解析：选D。由对话的语境可知，正确答案为D，ignore sb.没理睬某人。