C.Being surprised D.To be surprising 

　　2)The research is so designed that once __________ nothing can be done to change it.

　　A.begins B.having begun

　　C.beginning D.begun 

　　3)____________ in front of so many people,she did not know what to say.

　　A.Speak B.Speaking 

　　C.Spoken D.To speak

　　4)On hearing the news that his father returned from abroad,Jack got up quickly,________ the breakfast ________.

　　A.leaving;unfinished B.leaving;unfinishing

　　C.left;unfinished D.left;unfinishing

　　5)__________ such heavy loss,the foreign business didn't have the courage to go on.

　　A.Having suffered B.Suffering

　　C.To suffer D.Suffered 

　　答案与解析:

　　16.1)interested,interesting　2)opened,opening　3)singing,sung　4)exciting,excited 

　　17.1)B　过去分词修饰人,表示人因为受到外界刺激而产生的反应;现在分词与物连用,表示该物具有引起某种变化的性质。形容词短语surprised and happy作伴随状语,修饰后面的句子。

　　2)D　这句话补充完整后是这样的:The research is so designed that once(it is)begun nothing can be done to change it.在这里it的所指很清楚,省去后丝毫不影响理解,句子结构却更简练。

　　3)B　现在分词作状语,表示伴随的动作:在那么多人面前说话,她不知说什么。

　　4)A　leaving短语在句中作结果状语,unfinished是形容词,意思是"未完成的"。

　　5)A　the foreign business与suffer之间存在主动关系,且suffer的动作发生在主句动作之前,因此要用动词-ing的完成式。