Grammar and punctuation mistakes can make your writing seem uneducated and careless, but correcting those mistakes is not that difficult if you keep these rules in mind.
It might not be a surprise to you that comma errors are at the top of the top of the “Mistakes” list (along with misuse of “tricky” words).
1. Commas separating independent clauses
When two independent clauses are joined by a coordinating conjunction (and, or, nor, for, so, yet, but), you need a comma:
• Sally went to school, and her father went to work.
• Jesse didn’t feel well, so he stayed home.
2. Commas separating dependent and independent clauses
When a dependent clause precedes an independent clause, you need a comma:
• If I leave work early today, I can get to the matinee.
When a dependent clause comes after an independent clause, you don’t need a comma:
• I can get to the matinee if I leave work early today.
3. Commas separating introductory words or phrases
An introductory phrase or group of words needs a comma unless it’s very short.
• On second thought, let’s get pizza.
• Tonight we’ll order pizza.
4. Sentence fragments
Every complete sentence requires a subject and a verb. Sentence fragments lack one or the other.
• Home on the range. (no verb)
• Ate some chicken for lunch. (no subject)
5. Verb-subject agreement
Subjects and verbs must agree in person and number. This can be confusing when the subject and verb are separated by a group of words:
• Kylie, the girl in the orange dress and sneakers, is a junior.
• People who are intelligent often enjoy playing chess.
6. Colons and semi-colons
Colons introduce lists or specific definitions:
• Please buy these things at the store: matches, light bulbs, and cottage cheese. Semi-colons separate clauses that are closely related:
• We take the same classes in school; we both love biology.
7. Repeated subjects or objects
Other languages allow a subject or object to be repeated in its own clause, but English doesn’t allow this. In other languages, this is correct:
• The purse that had been stolen it was found.In English the correct sentence must be
• The purse that had been stolen was found.
The same is true for objects:
Incorrect:
• The little dog chased the car that his owner was riding in it. Correct:
• The little dog chased the car that his owner was riding in.
8. Parallelism
Items in a series should be the same. When your using nouns, verbs, adjectives, etc. in a series, they should all agree.
Incorrect:
• Sam loves skiing, running track, and basketball.
Correct:
• Sam loves skiing, running track, and playing basketball.
9. Apostrophes
Many nouns and pronouns add s to form the plural and ‘s to show possession. It versus it’s is a very good example since lots of people make a mistake with this pronoun.
• It’s means It is – It is a beautiful day.
• Its means ownership – The computer was left on the bus by its owner.
10. Quotation Marks
Quotation marks indicate direct quotations or exact statements of others. Indirect statements, or making reference to what someone said doesn’t require quotation
marks.
• Mom told Dad, “Please come home early from work tonight.”
• Mom asked Dad if he would please come home early from work tonight.