I heard the girl singing a song,为什么是用heard

I heard the girl singing a song,为什么是用heard I heard a girl singing in the next room 改为同义句 I heard that a girl ___ ___in the next room I heard the girl---（ sing)in the nest room yesterday evening. I heard a girl singing in the next room heard 和 singing在句中用法和原因 I heard the girl ___(sing) in her room at this time last night. I don't know lucy,but I the( )girlA heard B knew about C learned D heard ofI don't know lucy,but I ( )the girl I heard a girl singing in the next room .（句型转换） I_ _ _ _in the net room. The girl cried ( ) (sad) when she heard the bad news. The girl that I The Girl I wanna Have you heard of the girl ___(call) Helen? I often hear the girl-----next door.when ipassed the door,I heard her---just now.A.sing ;singing B sings:sing Yesterday I Heard The Rain 歌词 The Saddest Song I Ever Heard 歌词 I Heard The Sound Of Voices 歌词 I Heard It Through the Grapevine 歌词 I often heard () (sing) in the room I ( ) never ( ) of the girl.我从未听说过这个女孩.为什么不能用would never do我知道填 have heard，但为什么不能用would never hear