书面表达用英语怎么表达？

This expression is used mainly in speech, not in writing.

这种表达主要用于口语，而不是书面语。

The course teaches students to avoid ambiguity and obscurity of expression.

这门课程教学生避免表达上的模棱两可、含混不清。

Try to put a little more expression into it!

尽量注入更多的感情！

Freedom of expression is a basic human right.

言论自由是基本的人权。

The expression in her eyes told me something was wrong.

她的眼神告诉我出事了。