空间的零件有长、宽、高三个方向的尺寸,但每个视图只能表示()个方向的尺寸。
A.两
B.三
C.四
D.五
参考答案:A
用所给词的适当形式填空。
1. The red skin is (small) than the blue one.
2. She _____ (go) to the cinema with her classmates tomorrow evening.
3. It's Children's Day. All the students are very ___ (excite).
4. Your classroom is on the (four) floor (层).
5. She wants _ (buy) a new pen.
6. It often (rain) in summer.
7. Sometimes they _ (not have) lunch at home.
8. Look! The bus ___ __ (come).
9. He _ (make) many cakes for his friends yesterday.
10. (be) there any tea in the cup?
在三角形连接的对称电源或负载中,线电压等于 倍相电压。( )