He______ on this paper for ten minutes but he______only about sixty words.

A．will have worked, has written

B．worked, has written

C．has been working, has written

D．will be working, works

国际多式联运就其运输方式的联合而言( )。

A．必须有一程是海运

B．不必是海运与其他方式的联合

C．第一程必须是海运

D．第一程不必是海运，第二程以后必须包括海运