在取样测定法测酶活力中，通常用下列哪种物质终止酶促反应（）
A.氢氧化钠
B.氨试液
C.三氯醋酸
D.稀醋酸
E.磷酸铵
参考答案：C
句型转换。
1. He studies at No.1 Middle School. (改为否定句)
He _________ _________ at No.1 Middle School.
2. He plays basketball very well. (改为同义句)
He is _________ _________ playing basketball.
3. My brother walks to the school every day.(改为同义句)
My brother goes to school __________ _________ every day.
4. She never goes roller skating. (对划线部分提问)
__________ _________ does she go roller skating?
5.There is some bread on the table.(改为一般疑问句)
_________ there _________ bread on the table?
供电企业的封印装备一般使用在哪能些工作中？
