With a travelling speed of up to 350 kilometres per hour, the railway to be built between Beijing and Shanghai _______ the journey time from 12 hours to 5 hours．

A．cuts

B．will cut

C．is cutting

D．has cut

（）等属于课时环节教学模式。

A.影像电教法

B.参观法

C.示范—训练模式

D.讨论法

E.指导—发展模式