Books in French, with jokes about English (7)
I believe the answer is:
engages
'books' is the definition.
(book can mean to book or engage someone's services)
'in french with jokes about english' is the wordplay.
'in french' becomes 'en' ('in' in French).
'with' means one lot of letters go next to another.
'jokes' becomes 'gags' (gag can mean a joke).
'about' is an insertion indicator.
'english' becomes 'E' (abbreviation).
'gags' going around 'e' is 'gages'.
'en'+'gages'='ENGAGES'
(Other definitions for engages that I've seen before include "books" , "Employs, hires" .)