缺小品詞to
　�、� 不定式充當各種成分，一般都不能缺少 to。如：
　　She went there ∧ (to) see her mother.
　　He asked me not ∧ (to) go there.
　　I have something important ∧ (to) tell you.
　�、� make, let, have, see, hear, notice, observe, watch 等動詞變成被動語態(tài)時，充當主語補足語的不定式前的 to需還原。如：
　　She was made ∧ (to) do heavy work.
　　The blind man was seen ∧ (to) cross the street.

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