人患重感冒时,往往用嘴呼吸,早上醒来会觉得嗓子非常干,这说明鼻腔能够
把多项式ac-bc+a2-b2分解因式的结果是( )
关于光现象,下列说法正确的是( )
This is a cat.
It's my pet.
Her name is Lylie.
She's clever.
She likes fish.
I like her very much.
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