型钢轧机是以（）命名。
A．轧辊工作辊径
B．成品轧机轧辊公称直径
C．第一架轧辊公称直径
参考答案：B
根据句意完成单词。
1. My mother's brother is my ______.
2. Helen _______ my aunt. My aunt is Lucy.
3. Nina's father and mother are her ______.
4. These are pens and ______ are pencils.
5. ______ me, is this your sister?
硫酸二甲酯可用作（）。
A、烷基化剂
B、酰基化剂
C、还原剂
D、氧化剂
