throw的过去式和过去分词

　　Recent research has thrown new light on the causes of the disease.

　　最近的研究可以使人进一步了解导致这种疾病的原因。

　　It seems such a waste to throw good food away.

　　把好的食物扔掉似乎太浪费了。

　　The house had been thrown open to the public.

　　这所宅院已向公众开放。