改为反问句：Do you know fish can sleep with their eyea open?

你写错了一个词，是eyes,不是eyea
Don't you know fish can sleep with their eyes open?

补充说明：
反问句由be/情态动词/助动词的否定缩略式开首构成，表示“难道……不……？”
如：
Aren't you a worker?难道你不是工人吗？
Don't you know?难道你不知道吗？
Can't you swim?难道你不会游泳吗？

Don't you know fish can sleep with their eyes open?

Don’t you know fish can sleep with their eyea open?