30. Last month, the Japanese government expressed their thanks for the aid they ______ from China.

A. receive                 B. are receiving         C. have received        D. had received

分析：D。本句意為：上個月，日本政府表達了他們從中國得到的援助。從時間上看，應該是先得到援助，然后才表示感謝，由于“表達”用的是一般過去時（expressed），所以“得到援助”就應用過去完成時（had received）。又如：

He was conscious that he had annoyed his boss. 他意識到他惹煩了上司。

Although he had only entered the contest for fun, he won first prize. 盡管他參加這次競賽只不過是鬧著玩兒而已，卻贏得了頭獎。

31. We arrived at work in the morning and found that somebody ______into the office during the night.

A. broke                   B. had broken            C. has broken            D. was breaking

分析：B。從時間上看，肯定是先有人在夜間闖進了辦公室，然后才會有人發現這個情況。由于“發現”用的是一般過去時（found），所有夜間“闖進”辦公室，就應用過去完成時（had broken）。又如：

I went home directly I had finished work. 我一干完工作就回家了。

32. By the time Jack returned home from England, his son ______ from college.

A. graduated             B. has graduated        C. had been               D. had graduated

分析：D。本句意為：當杰克從英格蘭返回家時，他的兒子已經大學畢業了。顯然，兒子大學畢業在先，杰克返回家在后。而“返回”家用的是一般過去時（returned），故兒子大學畢業要用過去完成時（had graduated）。又如：

I read that he had resigned. 我看到他已辭職的報道。

The weather was rather worse than I had expected. 天氣要比我預料的還壞。

33. She was surprised to find the fridge empty; the child ______ everything!

A. had been eating     B. had eaten              C. have eaten            D. have been eating

分析：B。句子前面說她發現冰箱是空的，她感到很吃驚，而冰箱為什么是空的呢？是因為里面的東西都被孩子們吃掉了。顯然，孩子們吃掉冰箱里面的東西在先，她發現這個情況在后，而She was surprised to find the fridge empty用的是一般過去時，故孩子們“吃掉”冰箱里面的東西要用過去完成時（had eaten）。又如：

That the attempt to save her had failed soon became widely known. 想救她而未救成，此事不久已盡人皆知。

I was surprised when I saw the farm. I had imagined it to be much bigger. 我看到那個農場時很吃驚，我原認為會它會大得多。

34. —What a mistake!

—Yes. I ______ his doing it another way, but without success.

A. was suggesting      B. will suggest           C. would suggest       D. had suggested

分析：D。根據句中的What a mistake（真是個愚蠢的錯誤）和without success（沒有成功）可知，“沒有成功”的情況已經發生了。為什么說是個愚蠢的錯呢？為什么沒有成功呢？原來是說話者建議他用另外一種方法來做，很顯然，“建議”他用另外一種方法來做在先，他照去做并且沒有成功這件事在后，所以“建議”這個動作應用過去完成時（had suggested）。又如：