543] He is too careless and he _______ keys.

[译文] 他太粗心了，老是掉钥匙。

　 A. always lost 　 B. always loses

　 C. is always losing 　 D. will always lose

[答案及简析] C。 is always doing sth. 是一个句型，"老是做…"。

542] Please write your composition ________ line to leave space for the teacher’s correction .

[译文] 请隔行写你的作文以便留下空间供老师评改。

　 A. one another 　 B. every other

　 C. any other 　 D. each other

[答案及简析] B。 every other line 隔行。

541] _______ are the days when the teachers were looked down upon .

[译文] 老师被瞧不起的日子一去不复返了。

　 A. Gone 　 B. Go

　 C. To go 　 D. Going

[答案及简析] A。 Gone are the days when…是一个句型。

540] Mr. Wang was such a good teacher _______ the students love and respect.

[译文] 王老师是一个受到学生热爱和尊敬的好老师。

　 A. who 　 B. whom

　 C. that 　 D. as

[答案及简析] D。 such…as..引导的定语从句。

539] Until the present century, ________ demand for natural gas.

[译文] 直到本世纪，对天然气的要求几乎没有。

　 A. little 　 B. and little

　 C. there was little 　 D. was there little

[答案及简析] C。 there be…句型本身就是倒装结构，不需要再倒装。

538] By the end of this year, we _____ 2000 English words.

[译文] 到本年尾，我们将记住2000个单词。

　 A. will learn 　 B. would learn

　 C. have learned 　 D. will have learned

[答案及简析] D。 在有by the end of 引导的短语中，句子的时态要用完成时态。

537] _______ knows the truth will tell you about it , I think .

[译文] 我想，知道真相的任何人都会告诉你的。

　 A. Who 　 B. No matter who

　 C. Whoever 　 D. B and C

[答案及简析] C。 此句有强调的意思，故选C。

536] The head engineer is in ________ the project .

[译文] 主任工程师负责这项工程。

　 A. his charge of 　 B. the charge of

　 C. charge of 　 D. one’s charge

[答案及简析] C。 in charge of　固定搭配，"负责"。

535] ______ began our new lesson.

[译文] 这样我们的新课就开始了。

　 A. But 　 B. Such

　 C. Thus 　 D. So that

[答案及简析] C。 副词Thus位于句首，要完全倒装。

534] I didn’t manage to do it _____ you had explained how.

[译文] 知道你解释了后我才能把此事做好。

　 A. until 　 B. unless

　 C. when 　 D. before

[答案及简析] A。 not …until..结构，"直到…才"。