消化道衰竭的首发症状为（）
A.出血
B.腹泻
C.呕吐
D.便秘
E.食欲缺乏
参考答案：A
OptiX10G设备不能与OptiX155/622/2500+设备对接。
Your shoes are worn out, you should get them _____, or go to buy a new pair. [ ]
A. to repair
B. repairs
C. repaired
D. will be repaired
