⑴Where are your parents?____                           A. Yes, I'd like some fruit.

⑵Is your brother sleeping in the room?____      B. They are at home. 

⑶Can I help you?____                                         C. She's playing the piano.

⑷Would you like some fruit?____                       D. No, I'm not.

⑸Can you see the red light?____                        E. She's singing.

⑹What is Helen doing?____                                F. Yes, please.

⑺Are you busy?____                                           G. No, I can't.

⑻What is she doing in the music room?____     H. No, he isn't.

下列属于生物的是（  ）

先化简，再求值：1＋ $\frac{2\text{x-}4}{（\text{x+}1）（\text{x-}2）}$ ÷ $\frac{\text{x+}3}{{\text{x}}^2\text{-}1}$ ，其中x＝6．