问题
选择题
Chinese President Hu Jintao called for an immediate cease-fire in Libya _____ an even worse humanitarian crisis in the country at the BRICS Summit in Hainan Province.
A．to prevent
B．to have prevented
C．preventing
D．having prevented
答案
答案：A
本题考查非谓语动词。to prevent用不定式表示目的性，to have prevented表示动作已经完成。所以选A。