A couple of small grammar fixes

Author: helenst

en/installation/README.md

@@ -2,9 +2,9 @@
 
 If you're doing the tutorial at home, not at one of the [Django Girls events](http://djangogirls.org/events/), you can completely skip this chapter now and go straight to the [How the Internet works?](../how_the_internet_works/README.md) chapter. 
 
-This is because we cover these things in the whole tutorial anyway, and this is just an additional page that gathers all of the installation instructions in one place. The Django Girls event includes one "Installation evening" when we install everything to not bother with it during the workshop, so this is useful for us. 
+This is because we cover these things in the whole tutorial anyway, and this is just an additional page that gathers all of the installation instructions in one place. The Django Girls event includes one "Installation evening" when we install everything so we don't need to bother with it during the workshop, so this is useful for us. 
 
-If you find it useful, you can follow through this chapter too. But if you wanna start learning things before installing bunch of stuff on your computer, skip this chapter and we will explain the installation part to you later on.
+If you find it useful, you can follow through this chapter too. But if you wanna start learning things before installing a bunch of stuff on your computer, skip this chapter and we will explain the installation part to you later on.
 
 Good luck!