先化简，再求值：（2+a）（2﹣a）+a（a﹣5b）+3a⁵b³÷（﹣a²b）²，其中ab=﹣$\frac{1}{2}$．

            means activities of teaching.

A.It's my brother's.

B.No, I didn't.

C.I'm sorry.

D.Yes, I do.

E.I got up at seven thirty.

(____)1. Did you watch TV last night?      

(____)2. Do you usually help your parents?

(____)3. You shouldn't go to school late.   

(____)4. When did you get up this morning?

(____)5. Whose coat is it?                  

—But I still remember the story, believe it or not,_____we got lost on a rainy night.