I thought I must help him.

我想我必须帮助他。

youdao

I must help him.

我得帮助他！

youdao

I must help him to take care of the patient.

我必须帮助他照顾病人。

youdao

I must help him to take care of the patient.

我必须帮助他照顾病人。

youdao