Herald is bent on being heard (4)
I believe the answer is:
bode
'herald' is the definition.
The definition and answer can be both to do with communicating as well as being verbs in their base form.
Perhaps you can see an association between them that I can't see?
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for bode that I've seen before include "Augur (well or ill)" , "Waited" , "predict" , "Presage" , "Portend, foretell" .)