English

I learnt proper English some years ago. Strict, in the grammar sense, English. However, more and more, I see my abilities being deteriorated due to the internet. Even native speakers make constant mistakes, being some horrendous, which from those, unfortunately, I am beginning to be a victim, as I can notice them in my own speaking.

Would someone mid recommending a good book I can download from which I can revise some concepts?
Also, is there any online resource for prepositions (these I always had trouble with)?

Thank you, /lang/

>>25
>But how would someone whose first language isn't English be able to distinguish between something "awkward" or not?
Experience.

>Actually, what makes a sentence "awkward", in the first place?
Unnecessary commas, for one. Fluff, unnatural wording, phrasing, syntax, word choice, etc.