煤矿井下电气管理要求，电缆悬挂整齐，（）清洁整齐。
A.设备硐室
B.机房设备
C.设备记录
参考答案：A
We _______ basketball on the playground when it _______ to rain. [ ]
A. played, began
B. were playing, began
C. played, was beginning
D. were playing, was beginning
经甘油一酯途径合成甘油三酯主要存在于（）
A.肝细胞
B.脂肪细胞
C.小肠黏膜细胞
D.乳腺细胞
E.胰腺细胞
