气腿的作用是支撑()并为凿岩机提供推进力。
A、钎杆
B、凿岩机
C、风管
D、风带
参考答案:B
Mr. Reed made up his mind to devote all he had to ________ some schools for poor children.
A.set up
B.setting up
C.have set up
D.having set up
软件工程研究的内容主要包括:______技术和软件工程管理。