Fix a couple wording issues in trpl book

src/doc/trpl/README.md

@@ -11,7 +11,7 @@ navigate through the menu on the left.
 ## Basics
 
 This section is a linear introduction to the basic syntax and semantics of
-Rust. It has individual sections on each part of Rust's syntax, and cumulates
+Rust. It has individual sections on each part of Rust's syntax, and culminates
 in a small project: a guessing game.
 
 After reading "Basics," you will have a good foundation to learn more about

src/doc/trpl/hello-cargo.md

@@ -7,7 +7,7 @@ Rust projects, and so it is assumed that Rust projects will use Cargo from the
 beginning.
 
 Cargo manages three things: building your code, downloading the dependencies
-your code needs, and building the dependencies your code needs.  At first, your
+your code needs, and building those dependencies. At first, your
 program doesn't have any dependencies, so we'll only be using the first part of
 its functionality. Eventually, we'll add more. Since we started off by using
 Cargo, it'll be easy to add later.