1.You'd better have that bad tooth (be pulled) out.
为什么括号中不是pulled?如果你用被动来解释我觉得不通~~因为e.g:I want to make myself understood.这里为什么就不是be understood?
2.He spent as much time as he could (to teach) the child.
为什么不是teaching?前面不是有spend吗?
3.Ask the teacher, and he will tell you answer.
为什么开头用ask不是asking等其他非谓语动词而是一个谓语?那这个句子岂不是有两个谓语了?
分都给了
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