Do the two adverbial clauses mean the same thing in the sentences below?
Youíve been thinking of something else while Iíve been
talking/while I was talking to you about this machine.
They mean the same to me.
Originally Posted by joham
You’ve been thinking of something else while I’ve been
talking to you about this machine.
Given the present perfect progressive form in the first clause, I'd stick to the same in the second. We are talking about exactly the same time period in both clauses.