将坐标、方位角和高程由采区某一水平方向引向另一水平的工作,称为()。
参考答案:采区联系测量
根据括号里的要求改写句子。
1. The little child needn't be looked after by them. (改为主动句)
They ________ the little child.
2. Our English teacher often tells us to speak English in class. (改为被动句)
We ________ often ________ speak English in class by our Eng- lish teacher.
3. The room is used to play ping-pong by people. (改为主动句)
People ________ the room ________ ping-pong.
4. We saw a lot of students playing games on the playground. (改为被动句)
A lot of students ________ games on the playground.
5. Li Feng made the baby stop crying. (改为被动句)
The baby _________ crying by Li Feng.
原子吸收进行回收率测定时,加标量不得大于样品中待测含量的()倍。
A.1
B.2
C.3
D.4