Drag concatenate function

[chimaera15]

This is probably a stupid question and I tried searching but I'm not even sure how to formulate my search.

I have a list of services in column A and a list of cities in row 1:
detroit birmingham bloomfield
affordable
cheap
hauling

I'd like to concatenate each service with the product, but so far when I try: =CONCATENATE(A1,"",B1) and drag the cell across the entire row it changes to =CONCATENATE(B1,"",C1) instead of =CONCATENATE(A1,"",C1)

Is there any other way?

Thanks a million!

 

[Fowmy]

Include a $ before A and drag
=CONCATENATE($A1,"",C1)

 

[chimaera15]

Wow that was easy, just saved me hours of frustration.

Thanks!