进入中学后，小刚看到的都是一张张新面孔，感到有些孤单。于是他主动向同学介绍自己。[ ]
√
Why not _____ your teacher for help when you can't finish _____ it by yourself? [ ]
A. ask; write
B. to ask; writing
C. ask; writing
D. asking; write
紧线、撤线前，应检查（）。必要时应加固桩锚或加设临时拉绳。
A.拉线
B.桩锚
C.导线
D.杆塔
