He____(study) English very hard!答案为什么是studies,而不是does study?

He____(study) English very hard!答案为什么是studies,而不是does study? We study English very hard Lucy ( )(study) English very hard. jack studies english hard,jim doesn't study english hard Jack studies Engish hard.Jim doesn't study English hard he always _____(study) English very hard. How does study English? study hard English 对吗?但我看到网上都是 study English hard 为什么? we study English very hard.改为同义句 Tom said,"I study English very hard. " 变为间接引语 We study English very hard.(改为同义句） I am working hard to study english 对吗,如果对,study为什么不是进行时study