() 2. 1 think Aeveryone should do Btheir part Cto keeping our school clean.

下列各题中均有一处错误，找出并改正.

() 1. Our teacher Ataught us Bsing English songs Cyesterday.

12. Betty practiced playing the piano yesterday afternoon.

(用 at five yesterday afternoon 替换 yesterday aflemoon 改写句子) 

Betty the piano at five yesterday afternoon.

11. They were having dinner when it began to snow.(改为同义句) 

While they ，it began to snow.

10. I was practicing dancing at ten last night.(对划线部分提问) 。

 at ten last night?

9. Tom should press the sides of his nose.(对划线部分提问) 

 should Tom?

8. Mr. Brown advised me to get an X-ray.(对划线部分提问) 

  Mr. Brown advise you?

7. Jenny has a sore throat. (对划线部分提问) 

 Jenny?

6. 1 was sleeping at the time of the rainstorm.(改为否定句)

I at the time of the rainstorm.

5. 1 gave away some books to a children's home last year. (改为否定句)

I books to a children's home last year.