旅客中途下车恢复旅行时，在（）内由车站办理签证手续。
A.2h
B.6h
C.48h
D.车票有效期间
参考答案：D
Without electricity human life ________ quite different today.
A．is
B．will be
C．would have been
D．would be
如图所示的开瓶器
