Question

He can run ... better than I do. He is a professional runner.​

Answer 1

Answer:

As

Explanation:

Thanks...................

Answer 2

Answer:

(Since the question isn't informative, I'm assuming you need to connect the two sentences.)

He can run better than I do because he is a professional runner.

As he is a professional runner, he can run better than I do.

If the question is to fill in the blank then:

He can run much better than me. He is a professional runner.

Hope this helps!