.
“There is a great potential for the development of Sino-U.S. trade, ______ is in line with the interests of the two countries and their people,” Wu said
| A．which | B．who | C．that | D．as |
John waited at the bus-stop for nearly half an hour the bus finally arrived .
| A．when | B．as | C．before | D．while |
Only according to the directions can the medicine be quite effective .
| A．taking | B．taken | C．being taken | D．having been taken |
—I really don’t know how to thank you enough .
—.
| A．No problem | B．Think nothing of it |
| C．Not at all | D．It doesn’t matter |
—Mark broke his leg when he was playing football .
—was that ?
| A．Since when | B．Since when ago | C．How long | D．How long ago |
The brake of your bicycle has come loose . You’d better it .
| A．settle | B．fix | C．pick | D．correct |