This is my first post here at Sitepoint. I have a WordPress website for a network of TOEFL teachers in Saudi Arabia. It ranks high for my targeted key phrases, but it occasionally gets penalized (I think). I noticed a drop twice in the last few months. Both times from top ten places to 30s or even 100+ places.

I checked my outgoing links and didn't find any "bad neighborhoods". I checked by Keyword density levels and didn't find anything. How can I know why google has penalized me? Maybe you can see something I don't know about. Thanks for your time!

Here's the website: