I heard him sing a song in the next room just nom .(改为同义句）
问题描述：
I heard him sing a song in the next room just nom .(改为同义句）
He ( ) ( )( ) sing a song in the next room just nom.
答
He ( was ) ( heard )( to ) sing a song in the next room just now.
此为主动语态变为被动的几个特殊情况之一
① 有些动词在主动结构中,后面接不带to的不定式,但如果改为被动,则需把省略的to加上,这类动词有 [let,make,have,help]和感官动词[feel,see,hear,watch,look at,listen to],如：The boss made my grandfather work 10hours a day.改成My grandfather was made to work for 10 hours a day.