could中文一般怎么回答

　　The operation could prolong his life by two or three years.

　　这次手术可使他多活两三年。

　　Events could have developed in a dramatically different way.

　　事情本来可以发展成另一种样子。

　　You could see from his face that he was lying.

　　从他的表情上你可以看出他在说假话。

　　Could you give me a bed for the night?

　　今晚你能给我弄个睡的地方吗？

　　No one could have foreseen things would turn out this way.

　　谁都没有预料到事情的结果会这样。