Update README.md

Author: monkstone

README.md

@@ -4,8 +4,8 @@ A port of [Filters4Processing][] to ruby-processing
 A growing collection of pixel shaders ported to Processing to be used with the `filter()` function. Most of these shaders come from the excellent [Shadertoy](https://www.shadertoy.com) by Iñigo Quilez.
 
 ### To run / watch shader sketches 
-NB: since ruby-processing-2.6.11 glsl files are also _watched_, so you can edit the shader running with watch mode,
-and it will automatically reload when you save your changes...
+NB: since ruby-processing-2.6.11 glsl files are also _watched_, so you can edit the shader of the sketch running in
+watch mode, and it will automatically reload when you save your changes...
 ```bash
 # autorun all sketches
 cd filters4ruby-processing