There are countless grammar rules and writing guidelines; below are eight easy rules to help you write effectively.
Rule 1. Use concrete rather than vague language.
Vague: The weather was of an extreme nature on the west coast.
Concrete: California had very cold weather last week.
Rule 2. Use active voice whenever possible. Active voice means the subject is performing the verb.
Active: Barry hit the ball.
Passive: The ball was hit.
Notice that the responsible party may not even appear when using passive voice.
Rule 3. Avoid overusing there is, there are, it is, it was, and so on.
Example: There is a case of meningitis that was reported in the newspaper.
Correction: A case of meningitis was reported in the newspaper.
Even Better: The newspaper reported a case of meningitis. (Active voice)
Example: It is important to signal before making a left turn.
Correction: Signaling before making a left turn is important.
Signaling before a left turn is important.
You should signal before making a left turn. (Active voice)
Example: There are some revisions which must be made.
Correction: Some revisions must be made.
Even Better: Please make some revisions. (Active voice)
Rule 4. To avoid confusion, don't use two negatives to make a positive.
Incorrect: He is not unwilling to help.
Correct: He is willing to help.
Rule 5. Use similar grammatical form when offering several ideas. This is called parallel construction.
Correct: You should check your spelling, grammar, and punctuation.
Incorrect: You should check your spelling, grammar and punctuating.
Rule 6. If you start a sentence with an action, place the actor immediately after or you will have created the infamous dangling modifier.
Incorrect: While walking across the street, the bus hit her.
Correct: While walking across the street, she was hit by a bus.
She was hit by a bus while walking across the street.
Rule 7. Place modifiers near the words they modify.
Incorrect: I have some pound cake Mollie packed in my lunch bag.
Correct: In my lunch bag, I have some pound cake that Mollie baked.
Rule 8. A sentence fragment occurs when you have only a phrase or weak clause but are missing a strong clause.
Example of Sentence Fragment: After the show ended.
Example of Sentence: After the show ended, we had coffee.
Source: Blue Book of Grammar