First soothe and frequently calm (6)
I believe the answer is:
soften
'calm' is the definition.
The definition and answer can be both related to change as well as being verbs in their base form.
Maybe they are linked in a way I don't understand?
'first soothe and frequently' is the wordplay.
'first soothe' becomes 's' (1st letter of 'soothe').
'and' says to put letters next to each other.
'frequently' becomes 'often' (synonyms).
's'+'often'='SOFTEN'
Can you help me to learn more?
(Other definitions for soften that I've seen before include "Become gentler" , "Make less hard or become less severe" , "To moderate" , "Tone down" , "become less rough" .)