A and AN mean the same thing. A is used before words beginning with a consonant (any letter except a, e, i, o, or u) and AN is used before words beginning with a vowel: a, e, i, o, or u; or in front of a silent h. So basically, if a word has a...
The use of the apostrophe ( ‘ ) is so misunderstood. It has 2 major uses. (1) To denote the possessive by adding (’s) eg. the doctor’s office, Christine’s book and (2) To denote a contraction or missing letters eg. don’t (do not), she’ll (she will).It should not be used in words that are simply plurals such...