If you really have to leave during the meeting, you’d better leave _____ the back door[ ]

The Yellow River is one of _____ rivers in China.

ill be removed from his position if he doesn’t come to work on time－Surely,butJohn isn’t so foolish________ not to realize that

下面各句中加点词语的解释有误的一项（ ）

The earthquake in Japan, measuring 9.0 on the Richter Scale, was so violent _______ cause a series of explosions of the nuclear reactors in several power stations