If a picture is worth a thousand words, proofreading is probably worth even more. In a country like Turkey where the fascination for using English in advertising usually far outstrips the ability and attention to detail, checking something before sending it to print is priceless. Here are some fine examples of Turklish and the importance of proofreading.
A. How well do you know your prepositions?
B. It must be an exhausting business!
D. Here’s one for the culture vultures and the eagle eyed.
F. What, they don’t have fresh, new coffee?
If you’re an English teacher and you need a handy go to reference, or a student wanting easy to understand explanations and exercises, you can’t go past Basic Grammar in Use by Raymond Murphy.