1.The political future of the president is now hanging by a __.　　
　　A thread
　　B cord
　　C string
　　D rope
　　
2.The question is still__ discussion.　
　　A in
　　B by
　　C for
　　 D under　　
　　
3.We managed to reach the top of the mountain, and half an hour later we began to __.
　　A ascend
　　B descend
　　C decline
　　D plunge　　
　　
4.To survive in the intense trade competition between countries, we must__ the qualities and varieties of products we make to the world-market demand.　　
　　A improve
　　B enhance
　　C guarantee
　　D gear
　　
5.There has been a __ lack of communication between the union and the management.
　　A regretful
　　B regrettable
　　C regretting
　　D regretted

來源:可可英語 http://www.ccdyzl.cn/tem4/200906/75186.shtml