Gerard's visit to mother-in-law lasted too long! (7,2)
I believe the answer is:
dragged on
'long' is the definition.
The answer and definition are not the same part of speech. However, adjectives and past participle verbs can sometimes mean the same thing.
'gerard's visit to mother-in-law lasted too' is the wordplay.
I cannot quite see how this works, but
'visit' could be 'do' ('do' can mean to visit an attraction or landmark) and 'do' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for dragged on that I've seen before include "continued tediously" , "failed to finish" .)