句型转换。

1. Math is my favorite subject.(同义句)

I ______ math ______.

2. She loved playing soccer when she was ten.(划线部分提问)

______ did she ______ when she was ten.

3. Turn out the light.(否定句)

______ ______ out the light.

提高饲料蛋白质利用率的原理与措施。