Question

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

Answer 1

A

考查非谓语动词。呼吁停火是为了阻止更大的人为灾难。不定式表目的和将来。所以用to prevent。而to have prevented表明阻止发生在呼吁之前，所以不正确。