I'm going to practice really hard.

我打算非常努力地练习。

I'm going to study math really hard.

我打算努力学习数学。

And if you work really hard, you'll be famous.

如果你非常努力，你会出名的。

When we got to the top, it was raining really hard.

当我们到达山顶时，雨下得很大。

He sighed and said, This is really hard.

他叹息着说：“这真是太难了。”

She sighed and said, This is really hard.

她感叹地说：“这真是太难了。”

This project was really hard, but we did it.

这个项目真的很辛苦，但我们做到了。

Some kids press down really hard when they write.

有些孩子在写作时非常用力。

It can be really hard for them to stick to a diet.

对他们来说，坚持节食是很困难的。

Although Simon has done well in his studies, he still works really hard.

尽管西蒙学习成绩很好，但他仍然非常努力。