Birds fly是主谓结构.那 Birds can fly 是什么结构?

Birds fly是主谓结构.那 Birds can fly 是什么结构? The birds can ( )(fly). Can birds fly?----- Yes,() can All birds can't fly. birds can fly,birds fly两者的区别. All birds can't fly=Not all birds can fly.吗?All birds can't The birds can't fly without w_____ __ birds can fly in the sky. Birds can't fly without w____. not all birds can fly翻译 fly,birds,can,they,can't怎么排序 Can you see the birds _______(fly) above the trees?