Keep one as a master copy for your own reference and circulate the others.一盘留作母带自用，其余的都分发出去。The frozen snow was so slippery that it was hard to keep one's feet.冰雪溜滑,人们很难站稳.It is difficult to keep one's balance ...
Objective To study the CT findings of dermoid cyst of the orbit.目的分析眼眶皮样囊肿的CT表现.In the late 1970s Laos fell within the orbit of Vietnam and the Soviet Union.20世纪70年代末，老挝被纳入了越南和苏联的势力范围。Pluto has an elliptic orbit.冥王星的轨道是椭...