Speak volubly in English very loudly to get through (6)
I believe the answer is:
effuse
'speak volubly' is the definition.
(to effuse is to speak volubly or passionately)
'english very loudly to get through' is the wordplay.
'english' becomes 'e' (abbreviation).
'very loudly' becomes 'ff' (short for fortissimo, 'very loud' in music).
'to get through' becomes 'use' (get through can mean to gradually use something up).
'e'+'ff'+'use'='EFFUSE'
'in' is the link.
(Other definitions for effuse that I've seen before include "Pour or spread out" , "Pour forth (words)" , "Gush" .)