I study harder than Peter.

我比彼得学习更努力。

OK, I must study harder then.

好的，那我必须更加努力学习。

I will study harder for the next exam.

下一次考试我一定会更努力。

From then on, she decided to study harder.

从那时起，她决定更加努力学习。

He needed to study harder to pass the exam.

他需要的更加努力学习才能通过考试。

He promised his parents that he would study harder.

他承诺父母会更加努力学习。

She advises her friend to study harder for the exam.

她建议她的朋友更努力地为考试学习。

The teacher's moral encouragement made me study harder.

老师的精神鼓励让我更加努力学习。

The teacher implicitly suggested that we should study harder.

老师含蓄地建议我们应该更加努力学习。

The teacher's exhortation to study harder motivated the students.

老师的劝告激励了学生们更加努力学习。