I do believe I have all the skills that you are looking for in a freelancer to do your project!
I am a Communicative English & Soft Skills trainer by profession, so you can rest assured about the quality of my English language.
I train young aspirants on the aspects of product features & benefits and the nuances of marketing, so your need for someone with the knowledge of marketing is taken care of by me.
And regarding facebook? Well, this is one place I go to every day to catch up with friends and colleagues.
So, I am pretty confident that I fulfil all your requirements. In fact my freelance candidature is what you could call "a-three-in-one" package!
I would appreciate any further details on the project from you sent directly to my inbox.