1.    Confusion of lay and lie. Lay is a transitive or action verb and requires an object to receive
        its action. (Example: Please lay the book on the table. Lay your head on my shoulder.)
        Lie is an intransitive verb and is not associated with an object. (Example: I'm tired and need
        to lie down. Lie on the cot to rest). The past tense of lie is lay. (Example: Exhausted he
        lay on the ground for a day and a night). Hence the confusion. Do not say that you will
        lay down if you mean that you are going to recline or place your body in a prone position.
        Rather say you are going to lie down because your body is not considered an object and
        does not take the action verb lay.

2.    Confusion of affect and effect. Affect and effect both function as nouns and verbs, but
        affect is usually used as a verb while effect is more frequently used as a noun. As a verb
        affect means to influence or have an impact upon. (Example: Too much money chasing
        too few products will affect the cost of living. The bleak novel affected my mood for
        a day). As a noun effect refers to result or influence. (Example: What is the effect of too
        much money chasing too few products? The effect of the acid on the metal was
        devastating.) Effect is commonly misused for affect. Remember that effect or result is
        the outcome of affect or influence.

3.    Confusion of conscious and conscience. Both conscious and conscience are nouns and look
        much alike but in meaning they have nothing in common. Conscious, referring to a state of
        consciousness, means aware, cognizant, alert. (Example: I am conscious of the difficulty of
        the task ahead. He is conscious of his mistake). Conscience refers to a moral sense of
        right and wrong or of guilt. (Example: Her conscience got the better of her and she
        confessed her guilt. The perpetrators of the holocaust had no respect for human life,
        no conscience at all).

4.    Pronoun-Pronoun disagreement, particularly with everyone, anyone, someone. Everyone,
        anyone, someone are singular pronouns that take singular verb forms and singular pronoun
        forms. We do not say "Everyone are coming" or "Someone are special to me." It is just as
        incorrect to say "Did everyone get their coat?" or "Anyone who burns the flag should have
        their rights taken away." Do not use they or their to refer to everyone, anyone, or someone.
        Simply put, they and there are plural pronouns and do not go with the singular pronouns of
        everyone, anyone, and someone.

5.    Pronoun-Verb Disagreement. He, she, and it always take the singular form of a verb, never
        the plural. (Example: He does, she does, it does. Never say or write he don't, she don't,
        it don't). This is a serious breach of good usage that should always be avoided.

6.    Misuse of the apostrophe, especially with it. The apostrophe causes more trouble than
       any other mark of punctuation. It indicates possession and denotes contraction. (Examples:
       Jane's sweater. They won't be going to the dance). Before modern English, possession
       was indicated by the formation "The man his hat" rather than "The man's hat." Nouns almost
       always form the possessive by adding " 's " but the exception involves the pronoun it. The
       possessive form of it does not have the apostrophe. (Example: In hibernation the bear lost
       its fat.) It with the apostrophe is the contraction for it is. (Example: In hibernation the bear
       lost its fat). It with the apostrophe is the contraction for it is. (Example: It's cold in this
       room). Never use the apostrophe for the possessive form of it.

                                                                            -- Robert G. Blake