题目内容：

Hearing the 2008Olympic Games _____,all the people in beijing stadium burstinto cheers.
A.declared to be opened B.declaring to be opened C.declared open D .to be declared open

优质解答

这句话的考点如下：
hear sth.done:意思是 听说某事被做了,已经做了
hear sth.to be done:意思是 听说某事将要被做,还没做
听到2008年奥运会被宣布开幕,北京鸟巢全场观众欢呼了.
所以选C.