Update README.md

A minor typo.

README.md

@@ -841,8 +841,8 @@ and we get back:
 And that matches what we said in the type system section, that
 the `Query` type is where we will start! Note that the naming here
 was just by convention; we could have named our `Query` type anything
-else, and it still would have been returned here had we specified it
-was the starting type for queries. Naming it `Query`, though, is a useful
+else, and it still would have been returned here if we had specified it
+as the starting type for queries. Naming it `Query`, though, is a useful
 convention.
 
 It is often useful to examine one specific type. Let's take a look at