测定水的总硬度和钙硬度时都是用EDTA容量法,只是所选指示剂不同
参考答案:错
句型转换。
1. Our English teacher is from England. (改为同义句)
Our English teacher _____ England.
2. My father has been out of the work for two months. (就画线部分提问)
_____ has your father been out of the work?
3. Have you received a letter from your parents recently? (改为同义句)
Have you _____ your parents recently?
4. I feel tired. How about having a rest? (改为同义句)
I feel tired, _____ have a rest?
5. The baby didn't cry any more as soon as he saw his mother.(就画线部分提问)
When did the baby ______?
脚手架拆除前,应全面检查脚手架的()。
A、杆件连接
B、连墙杆
C、挡脚板
D、支撑系统