As for the languages I know I think to believe, that a subordinated clause comes in a chunk and not scattered throughout the main clause.
For instance:
I LIKE TO SING, while i slave away
while I slave away is the subordinated clause and in one continuous piece, there is nothing like:
- I while LIKE i TO slave SING away
Now I don't know if this contradicts some basic principle in linguistics, but a friend of mine,Aslan, who admittingly tends to be a crackpot, but has also proven to be smart, claims, that this is the case in one of the Balkan languages he speaks.
The example I provide is necessarily just wrong grammar I had to make up, to exemplify what I mean.