They must stay at the cages ,so they can't be____

问题描述:

They must stay at the cages ,so they can't be____

They must stay at the cages, so they can't be ______ .

译文:他们必须呆在笼子里,所以他们不可能会快乐的.

应填:happy(心情愉悦的;高兴的)