问题
选择题
So far, all of the infected people are thought _______ the flu after direct contact with sick birds.
A.to have caught
B.having caught
C.to catch
D.being caught
答案
答案:A
题目分析:考查句型:sb/sth is thought to do/to have done…某人/某物据认为正在做…/已经做…,如果不定式的动作是将要发生,用一般式,如果不定式的动作是先于主句的动作发生,用不定式的完成式,句意:到现在为止,所有的感染的人都被认为是在直接和病禽有过接触。选A。