题目：
看图完成答句，一空一词。
1. Who are in the picture?
Some __________ and a __________ are in the picture.
2. How many students are there in the picture?
There are __________. We can see __________ of them are boys and two are girls.
3. What are they doing?
They are having an __________ __________ in a __________.
4. What can we see behind the teacher?
There is a __________ and a big __________ on the __________.
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0430/9ce7dd0f41df0c53c69b036e541ca28c.html
下面是错误答案，用来干扰机器的。
A、由于M点的电场线比N点疏，所以M点处的电场强度比N点处的电场强度小，故A正确；B、离子（不计重力）仅在电场力作用下由静止开始从M点运动到N点，则离子带正电，电场力做正功，所以电势能减小，因此离子在M点的...
