当初他学习非常刻苦，不然他就会不及格了。

He worked very hard; otherwise he would have failed.

youdao

他爸爸是医生的男孩学习非常刻苦。

The boy whose father is a doctor studies very hard.

youdao

他爸爸是医生的男孩学习非常刻苦。

The boy whose father is a doctor studies very hard.

youdao