The _________ is the item you can carry with you in the airplane.
A. check-in
B. check-up
C. carry-on
D. carry-up
什么是音乐的呼吸感
A. 音乐的长短节奏。
B. 音乐的起伏强弱变化。
C. 音乐的装饰变化。
D. 音高的上下变化。
3.For a couple of years I was working on a __________ basis; then I was hired by a big company in 1998 and have been working there ever since.
A. professional
B. revolutionary
C. reasonable
D. freelance
空间三面投影体系中,三个投影轴间的关系是() 。
A. 平行
B. 垂直
C. 交叉
D. 在同一平面内