游标卡尺的下卡脚用于（）测量。
A.深度
B.内
C.外
D.长度
参考答案：C
看图回答问题。
1. --- How many computers are there ?
--- __________________________ .
2. ---What's this in English ?
--- ___________________________ .
3. --- What are these ?
4. --- Are these bikes ?
--- ______________________________ .
5. --- Is this a cat ?
--- ______________________________.
塑料制眼镜架
