condition as soon as possible.
答案：C 虚拟语气。Suggest 表示建议，命令，请求等语气的时候要用虚拟语气；Should+v.，应把C项is told改为should be told。
52. Nearly [three quarters of the surface] of the earth [are] covered
A B
with water, and [there] would be even less land [if] the polar icecaps
C D
were melt.
答案：B 主谓一致。主语虽然有四分之三修饰，但中心词表面是不可数名词，所应谓语动词用单数，即B项are改为 is。
53. The seventeenth century was one [which] many significant
A
[advances] [were made] [in both] science and philosophy.
B C D
答案：A 定语从句。Which在该句中应作时间状语，应该用in which。
54. No matter [whatever happens], we’re determined to [do our best]
A B
and [make] the experiment [a success].
C D
答案：A 连接代词。Whatever引导让不状语从句，含义相当于No matter what，所以Whatever和No matter what是重复的，应去掉Whatever，改成what 。
55. [Let’s not]waste time on [matters of no important]. We have other
A B
[vital] problems to [deal with].
C D
答案：B beof+n.结构。应把Important改为Importance。
Part IV Ctoze
What do we mean by a perfect English pronunciation? In one 56 there are as many different kinds of English as there are speakers of it. 57 two speakers speak in exactly the same 58 . We can always hear differences 59 them, and the pronunciation of English 60 a great deal in different geographical 61 . How do we decide what sort of English to use as a 62 ? This is not a question that can be 63 in the same way for all foreign learners of English. 64 you live in a part of the world 65 India or West Africa, where there is a long 66 of speaking English for general communication purpose, you should 67 to acquire a good variety of the pronunciation of this area. It would be 68 in these circumstances to use as a model BBC English or 69 of the sort. On the other hand, if you live in a country 70 there is no traditional use of English, you must take 71 your model some form of 72 English pronunciation. It does not 73 very much which form you choose. The most 74 way is to take as your model the sort of English you can 75 most often.
