同沉积褶皱的特点是（）。A、背斜顶部厚翼部薄B、背斜顶部薄翼部厚C、两翼倾角上陡下缓

_____ for the breakdown of the school computer network,Alice was in low spirits. [ ]

A. Blaming      

B. Blamed              

C. To blame            

D. To be blamed

“Where is Mother.” “She is in the kitchen. She _______ the housework all morning.”

A．is doing

B．was doing

C．has done

D．has been doing

瑞士位于中欧南部，哪几种语言为官方语言。（）

A．英语

B．法语

C．德语

D．意大利语

E．斯瓦希里语

竖向导管法的主要设备有（）承料漏斗、球塞、检查锤、测锤及射水设备等。