e.g. The frog is not a warm-blood animal. It’s a cold-blooded one. e.g. It’s a sad thing. Just forget it.e.g.--who’s that ? --It’s me. Open the door ,please .( )
代替前文提到的人/物/事情,在句中做主语或宾语.
人
I . 用作人称代词
(物 )
(事情)