做非谓语动词考题的常用技巧

确定非谓语动词时态方法很简单，那就是看非谓语动词所表示的动作是发生在谓语动词之前还是之后——若发生在谓语动词之前，则非谓语动词用完成式；否则，就用一般式。如：

______ to work overtime that evening, I missed a wonderful film. (重庆卷)

A. Having been asked B. To ask                 C. Having asked       D. To be asked

解析：答案为A。从时间上看，显然“被要求加班”在“错过看电影”之前，故非谓语动词要用完成式，据此可排除B和D；又因为动词 ask 与句子主语之间为逻辑上的动宾关系，由此可排除表示主动意义的选项C。句意为：由于那天晚上我被要求加班，所以我错过了一场很好的电影。又如：Having been his own boss for such a long time, he found it hard to accept orders from another. 自己当老板已经这么久了，他觉得难以听从别人的差遣。

三、确定非谓语动词语态的技巧

1. 根据句子的逻辑意义来确定

判断非谓语动词是要用主动式还是被动式，最简单的办法就是看非谓语动词的逻辑主语与非谓语动词之间是主谓关系还是动宾关系——若是主谓关系，则非谓语动词用主动式；若是动宾关系，则非谓语动词用被动式。如：

例1  China recently tightened its waters controls near the Huangyan Island to prevent Chinese fishing boats from ______ in the South China Sea. (福建卷)

A. attacking              B. having attacked     C. being attacked       D. having been attacked

解析：答案为C。考查 prevent sb (sth) from doing sth 结构，其意为“阻止某人（某物）做某事”。根据句意，Chinese fishing boats 与 attack 之间为被动关系，故动名词要用被动式，可排除A和B；再根据动作的先后关系，可排除D。句意为：中国最近加紧黄岩岛附近的水域控制来防止中国渔船在南海被袭击。又如：The most important trees were tagged to protect them from being damaged by construction machinery. 最珍贵的树木都被贴上了标签，以防被建筑机械毁坏。

例2  We’ve had a good start, but next, more work needs ______ to achieve the final success.(湖南卷)

A. being done           B. do                     C. to be done            D. to do

解析：答案为C。从意义上看，“工作”应该是需要“被做”，故要用不定式的被动式。不过值得一提的是，need也可后接动名词，此时则要用主动形式表示被动意义，所以如果将A改为doing，则也可视为正确答案。

2. 根据英语的表达习惯来确定

非谓语动词的主动与被动除根据句意来确定外，有时还要遵循英语的表达习惯，尤其是在有些表达中，尽管意义上是被动的，但形式上却要用主动式来表达。如：

This machine is very easy ______. Anybody can learn to use it in a few minutes. (辽宁卷)

A. operating        B. to be operating      C. operated              D. to operate

解析：答案为D。sth is easy to do 这类句式中，尽管句子主语与 easy 后的不定式具有动宾关系，该不定式习惯上却要用主动形式表示被动意义，而不能直接使用被动形式。又如：The shower is easy to install — it needs only to be connected up to the hot and cold water supply. 淋浴器很容易安装——只要接上冷热水就行。

3. 注意用过去分词表被动

例1  When ______ for his views about his teaching job, Philip said he found it very interesting and rewarding. (安徽卷)

A. asking                 B. asked                   C. having asked        D. to be asked

解析：答案为B。由于句子主语与动词 ask 之间为被动关系，故可排除 A 和 C；再根据句意和动作的先后关系，最佳答案应为 B。又如：When asked for your views about your current job, on no account must you be negative about it. 被问及你对自己目前工作的看法时，无论如何不要流露出消极情绪。

例2  After completing and signing it, please return the form to us in the envelope ______. (山东卷)

A. providing          B. provided          C. having provided  D. provide

解析：答案为B。由于 the envelop 与动词 provide 之间为被动关系，故只能选 B，其余三项均不表示被动关系。又如：Members shall enter the names of their guests in the book provided. 会员必须把所邀客人的名字登记在提供的本子上。