What I want to ask, is if you have a sentence like:

> He has bought his new car since 2015.

What will be the shape of that sentence if we begin it with "How many"? Which of these should it be?

> 1. How many years, has he bought his new car since?

> 2. How many years have been since he bought his new car?

> 3. How many years since he bought his new car?