关于主、被动语态的转化.1.Heisoftenheard(sing)intheroom.2,Isthesongsungbythechilden?(变主动语态.)thechildrenthesong?3.Twoyearsagoweusedthatmachinetomakeshoesforchildren.(变被动语态)Twoy

Question

关于主、被动语态的转化.
1.He is often heard ______ (sing) in the room.
2,Is the song sung by the childen?(变主动语态.)
__ the children ______ the song?
3.
Two years ago we used that machine to make shoes for children.(变被动语态)
Two years ago that machine ______ ______ _______ _________shoes for children.

Answer 1

1.hear sb do(经常干什么,或者干什么的全过程)、doing（正在……）
但是这类词是省略to的,所以在被动的时候要加上去
所以是to sing
2.Do ,sing
3.was used to make
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