Fix pixel shader typo in README (#8949)

Fixes a typo in the README regarding pixel shaders.

samples/PixelShaders/README.md

@@ -58,7 +58,7 @@ If your shader fails to compile, the Terminal will display a warning dialog and
 
 ## HLSL
 
-The language we use to write pixel shaders is called `HLSL`. It a `C`-like language, with some restrictions.You can't allocate memory, use pointers or recursion.
+The language we use to write pixel shaders is called `HLSL`. It's a `C`-like language, with some restrictions. You can't allocate memory, use pointers or recursion.
 What you get access to is computing power in the teraflop range on decently recent GPUs. This means writing real-time raytracers or other cool effects are in the realm of possibility.
 
 [shadertoy](https://shadertoy.com/) is a great site that show case what's possible with pixel shaders (albeit in `GLSL`). For example this [menger sponge](https://www.shadertoy.com/view/4scXzn). Converting from `GLSL` to `HLSL` isn't overly hard once you gotten the hang of it.