I have started listening to NHK-radio's new English program "Business Communication in Action" since this April.
I learned that conversation at meeting is not always more difficult than idle talk when it comes to English.
Two Jazz-men told me,
"Jazz improvisation is same as English conversation."
"Ad lib is not something which comes up with suddenly.
It is just a result on practicing hard, which emerges at solo performance."
In my view, English and music are quite similar.
Listening a lot of high quality phrases and practicing many times should lead us to improvement.