Do not use.

The word "use" usually needs to have something after it:

Do not use this medicine if the seal is broken.

But in written notices, people often leave out certain words that aren't necessary. Here are some examples of similar notices:

Beware of dog

Do not close

Please flush

Falling rocks ahead

Notices like these leave out objects ("this medicine"), "be" verbs ("are", "is", etc.) and articles ("the", "a").

This phrase appears in these lessons: