tom has finished his homework doesn't heTom has finished his work_英语解答

tom has finished his homework doesn't he
Tom has finished his work,_____he?
为什么用 hasn't
什么时候用doesn't
?讲解仔细点
例题

人气：127 ℃　时间：2019-12-08 19:22:57

解答

因为前面是现在完成时态,有助动词HAS,故要用hasn‘t,不能用doesn't.
比较：Tom finishes his work,doesn't he?