Fix comma+typo in MLIR toy tutorial chapter 3.

mlir/docs/Tutorials/Toy/Ch-3.md

 rule-based pattern-match and rewrite using table-driven
 [Declarative Rewrite Rules](../../DeclarativeRewrites.md) (DRR). Note that the
 use of DRR requires that the operations be defined using ODS, as described in
 [Chapter 2](Ch-2.md).
 
 ## Optimize Transpose using C++ style pattern-match and rewrite
 
 Let's start with a simple pattern and try to eliminate a sequence of two
-transpose that cancel out: `transpose(transpose(X)) -> X`. Here is the
+transposes that cancel out: `transpose(transpose(X)) -> X`. Here is the
 corresponding Toy example:
 
 ```toy
 def transpose_transpose(x) {
   return transpose(transpose(x));
 }
 ```
 
for(int i = 0; i < N; ++i) {
     for(int j = 0; j < M; ++j) {
        A[i][j] = B[j][i];
     }
   }
   sink(A);
 }
 ```
 
-For a simple C++ approach to rewrite involving matching a tree-like pattern in
+For a simple C++ approach to rewrite, involving matching a tree-like pattern in
 the IR and replacing it with a different set of operations, we can plug into the
 MLIR `Canonicalizer` pass by implementing a `RewritePattern`:
 
 ```c++
 /// Fold transpose(transpose(x)) -> x
 struct SimplifyRedundantTranspose : public mlir::OpRewritePattern<TransposeOp> {
   /// We register this pattern to match every toy.transpose in the IR.
   /// The "benefit" is used by the framework to order the patterns and process