1.Years ago we didn’t know this, but recent science _________ that people who don’t sleep well soon get ill. A. showed B. has shown C. will show D. is showing
解析：答案选 B。由表示对照的Years ago和recent可知，“以前不知”，但“现在已经证明了”，所以用现在完成时。
2.He was hoping to go abroad but his parents _________ that they won’t support him unless he can borrow money from the bank.
A. were deciding B. have decided C. decided D. will decide
3.The country life he was used to _________ greatly since 1992.
A. change B. has changed C. changing D. have changed
解析：答案选 B。since 1992这类时间状语通常与现在完成时连用。主句主语是the country life，句中he was used to是省略了关系代词that的定语从句。
4.He _________more than 5,000 English words when he entered the university at the age of 15. A. has learned B. would have learned C. learned D. had learned
1. Months ago we sailed ten thousand miles across this open sea, which _________ the Pacific, and we met no storms. A. was called B. is called C. had been called D. has been called
解析：答案选 B。因为这是客观事实，故用一般现在时。 注：有关一般现在时的另一个考点是，在时间状语从句和条件状语从句中，要用一般现在时表示将来意义，而不能直接用将来时态。此时要特别注意的是，命题人有可能会设置形式上与状语从句相似且容易混淆的宾语从句作为命题切入点。
2.“What would you do if it _________tomorrow?” “We have to carry it on, since we’ve got everything ready.” A. rain B. rains C. will rain D. is raining
3.As soon as he comes back, I’ll tell him when _________and see him.
A.you will come B. will you come C. you come D. do you come
解析：答案选 A。when 引导的是宾语从句，不是状语从句。