急性腹膜炎所致呕吐属于（）。
A.神经性呕吐
B.反射性呕吐
C.中枢性呕吐
D.胃肠源性呕吐
E.周围性呕吐
参考答案：B
把长30m的钢管按7：8分成两段，较长的一段是______m．
She said that it was the second time that I _____ the film. [ ]
A. have seen
B. saw
C. see
D. had seen
