23.

In some parts of London, missing a bus means _______for another hour.

A. waiting　　　 B. to wait　　　 C. wait　　　 D. to be waiting

[解析]　 mean doing sth.的意思是“意味着什么”。mean to do sth.的意思是“打算做什么”。译文：在英国的某些地方，赶不上公共汽车意味着要再等一小时。答案为A。　

22.

Prices of daily goods _______through a computer can be lower than store prices.

A. are bought　　　 B. bought　　　 C. been bought　　　 D. buying

[解析]　 goods是动词bought的逻辑宾语，所以用过去分词修饰表被动。答案为B。　

21.

　_______to sunlight for too much time will do harm to one's skin.

A. Exposed　　 B. Having exposed　　 C. Being exposed　　　 D.After being exposed

[解析]　 在非谓语动词中，用动名词或不定式来作主语，而分词和介词短语不能作主语，因此A、D被排除。在这个句子中，will do是谓语，缺少主语，要用动名词作主语。expose与one's skin是动宾关系，所以要用动名词的被动式being exposed。译文：在阳光下晒太长时间对人的皮肤有坏处。答案为C。

20.

Don't use words, expressions, or phrases　 _______ only to people with specific knowledge.

A. being known　　 B. having been known　　　 C. to be known　　　 D. known

[解析]　 know 与words, expressions, phrases是动宾关系，要用过去分词作定语，表示被动。having been known是现在分词完成时的被动式不能作定语。译文：不要使用只有具有专业知识的人才知道的词语。答案为D。

19.

Though　 _______money ,his parents managed to send him to university.

A. lacked　　　　 B. lacking of　　　　　 C. lacking　　　 D. lacked in

[解析]　 lack是及物动词，后接宾语money。his parents与lack是主谓关系，要用现在分词作状语。译文：虽然缺钱，他的父母亲还是想法让他上了大学。答案为C。　

18.

Quite a few people used to believe that disaster　 _______if a mirror was broken.

A. was sure of striking　　　　　　　 B. was sure of having struck

C. was sure to be struck　　　　　　　 D. was sure to strike

[解析]　 be sure of“对……确信，有把握”，主语必须是人。be sure to do sth“就要，一定会”，主语可以是人或物。动词不定式表示将要发生的事，意思是“就要……”。译文：过去很多人都认为如果镜子破了，一定会引起灾难。注意：be+形容词后接不定式的一般式，不用被动式。如：The problem is difficult for us to work out.我们很难做出这个问题。答案为D。　

17.

In order to gain a bigger share in the international market ,many state　 run companies are striving　 _______their products more competitive.

A. to make　　　　 B. making　　　　 C. to have made　　　　 D. having made

[解析]　 strive to do sth=try to do sth“非常努力做某事”，动词不定式作目的状语，表示努力的目的。译文：为了在国际市场上取得更大的份额，许多国有公司正努力使自己的产品具有竞争性。答案为A。

16.

-How do you deal with the disagreement between the company and he customers?

-The key ________the problem is to meet the demand ________ by the customers.

A. to solving ;making　　　 　　　　　　B. to solving ;made

C. to solve; making　　　　　　　　　 　D. to solve;made

[解析]　 to放在key的后面作介词，后接动名词；过去分词短语made by the customers作demand的定语。make与demand是动宾关系，所以要用过去分词。这句话的意思是“解决问题的关键是满足顾客的要求。答案为B。　

15.

The research is so designed that once　 _______nothing can be done to change it.

A. begins　　　 B. having begun　　　　 C. beginning　　　 D. begun

[解析]　 once begun在句子中作状语。begin可以作及物动词，意思是“着手”。译文：这项研究设计得那么好，一旦着手研究，就没有什么地方要更改的了。答案为D。　

14.

Having a trip abroad is certainly good for the old couple, but it remains　 _______　　　 whether they will enjoy it.

A. to see　　　 B. to be seen　　　 C. seeing　　　 D. seen

[解析]　 这是一个主语从句。it作形式主语，whether they will enjoy it作真正的主语。remain后接to do sth.作表语。see与主语从句是动宾关系，所以要用to be seen 作remains的表语。答案为B。