Signature of intransitive verbs; symbol

Sign; signal

Example: Please check it and sign here.

Please check it and sign here.

Signal ['siɡn? L] n. signal; Codeword; blasting fuse

Signal; symbol

Remarkable; Make conspicuous

sending signal

Example: Can you hear the signal?

Can you hear the signal?

Self-adhesion; label

Example: Teacher Ma, you should mark all the names under each picture.

Ms. Ma, you should write all the names at the bottom of each picture.

What matters is the difference in meaning, right? When you say a verb, you mean to mark it.