needs repairing===needs to be repaired
need和require等词后面加动名词必须用主动表示被动,但加不定式时照旧,该用被动还用被动.比如:these trees require(need) looking after carefully= these trees require(need) to be looked after carefully.
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常用:need/require +doing sth(=to be done)(此句型主语大多为物)
例:My room is a mess.It needs _____.
A to be tidying up
B.tidying up
C.to tidy up
D.tidied up
(答案为B)
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