Grammar Common Mistakes

1.- Comma use.
Def: The comma is use to separate elements, and sentences. This is a common mistake because if someone gets it wrong, it can change the whole sentence meaning.
Ex. Im gonna eat pasta, fruits, meat and vegetables.
Ex2. Martin, who is british, has to go to the party.
Rule: http://grammar.ccc.commnet.edu/grammar/commas.htm

2.- These and This.
Def: "This" is used to mean singular and "these" is use when plural.
Ex. These people are really noisy.
Ex2. This man needs to drive through there.
Rule(8): http://www.grammarbook.com/grammar/adjadv.asp

3.- Use of "a" and "an".
Def: "a" is used when the next word starts with a consonant. And we use "an" when the next word starts with a vowel.
Ex. Look! A cat
Ex2. That is an apple.
Rule: http://www.wikihow.com/Use-%22A%22-and-%22An%22-Correctly

4.- Don"t and doesn"t.
Def:  Doesn"t is used with the third person singular, like he she it. Don"t is used for other subjects.
Ex. It doesn"t matter anymore.
Ex2. His glasses don"t help him too much.
Rule: http://englishplus.com/grammar/00000203.htm

5.- Was and were.
Def: We use "was" when we are talking about singular. But we use were when we use plural.
Ex. He was drinking a coke
Ex2. They were playing soccer together.
Rule: https://sites.google.com/site/bluebloc/grammar/past-tenses/there-was-there-were