胃镜检查常见的并发症有（）
A.低氧血症
B.肿瘤转移
C.术后腹泻
D.心跳骤停
E.食管、胃肠穿孔
参考答案：A, D, E
You ______ shake hands when you meet someone for the first time in China. [ ]
A. would like to
B. are supposed to
C. want to
D. will
— Can you help me with the maths homework, mom?
— You can’t always ____ other’s help for your homework. Do it by yourself this time, Dear.
A．wait on
B．rest on
C．insist on
D．turn on
