Unit 3 Protecting our selves【典题精讲】单项填空［例 1］ There have been several new events _____to the program for the 2008 Beijing Olympic Games.A. add B. to add C. adding D. added［思路解析］本题考查非谓语动词。new events 与 add 是被动关系，故用过去分词作定语。答案是 D。［黑色陷阱］本题易误选 A 项，原因是有些学生会把 add to 看作谓语。［绿色通道］分词短语作定语时应视其与所修饰的词的关系而定，主动关系用现在分词，被动关系用过去分词。［例 2］Isn’t it time you got down to ______the papers?A. mark B. be marked C. being marked D. marking［思路解析］本题考查动词-ing 形式作宾语。答案是 D。［黑色陷阱］本题易误选 A 项，原因是有些学生会把 to 当作不定式符号。［绿色通道］to 是介词，后面应接动名词。又由于逻辑主语 you 和 mark 之间是主动关系，所以用动名词的主动形式。［例 3］In the waiting room, we found Tom ______at a desk, with his attention ______on a novel.A. sitting; fixing B. seated; fixed C. sit; fixing D. sitting; to be fixed［思路解析］本题考查过去分词作宾语补足语及 with 的复合结构。答案是 B。［黑色陷阱］本题易误选 A 项或 C 项，原因是不知道 Tom 和 seat 及 attention 和 fix 都是被动关系。［绿色通道］过去分词作宾语补足语时，表示被动关系。［ 例 4 ］ You can’t imagine what great trouble they have _______the problem_______.A. to solve; being talked about B. solving; discussingC. to solve; to talk about D. solving; being discussed［思路解析］本题考查固定短语 have trouble (in) doing sth 的用法及动词-ing 被动形式作定语。答案是 D。［黑色陷阱］本题易误选 A 项，原因是看不出 they have 作定语修饰 trouble,不知道固定短语 have trouble (in) doing sth。［绿色通道］The problem being discussed 是“正在被讨论的问题”之意。［例 5］—The housework is too much for me, Jack..—Sorry, but I can’t help _______it, Joan. I’ve got something important to do, you know.A. do B. doing C. to be doing D. havin...
