Unique. A thing is neither unique or not unique. Do not say, "more unique," "most unique," or "less unique."
United States. The definite article the should always precede this proper noun, which is singular when it refers to the nation and plural when it refers to the states.
Up. Do not use up after most simple verbs which are complete in meaning within themselves. Say close, open, settle, fold, and so on, rather than "close up," "open up," "settle up," "fold up," and the like. It is correct in some other cases, as, "His men brought up the rear," and "The Speaker summed up his remarks effectively."
Very, too. Do not use very and too in place of very much and too much.
Incorrect: The customer was very annoyed.
Correct: The customer was very much (or was much) annoyed.
Correct: The resort was too much (not too) advertised to remain exclusive.
Want to. Do not use in the sense of should or had better. "You should (NOT want to) take better care of yourself.
Way. (1) Colloquialism for away, as in "He is going way off."
Better: He is going far away.
(2) When used after an intransitive verb, it should be introduced by a preposition, as "When he talks in that way (NOT talks that way), I want to punish him.
When, where. Not to be used for that. "It was at the director's meeting that (NOT when or where) he tendered his resignation." "I read in the papers last week that (NOT where) Mr. Agudo was responsible for opening the park to the public."
Where . . . at. A vulgarism for where.
Incorrect: I don't know where I'm at.
Better: I don't know where I am.
Or: I am confused (or puzzled).
While. Too frequently used loosely or incorrectly. It means at the same time, as in the sentence: "He played the piano while the others read." It should not be used in place of conjunctions like whereas, but, and so forth. "You are interested, but (NOT while) I am not. " "He may leave if he wants to, whereas (NOT while) you had better remain and finish your work."
Who, which, that. Who refers to persons or to certain animals of distinction; which to animate or inanimate things or ideas; and that to people or things. Who and which are frequently preferred for non-restrictive clauses. That is occasionally preferred with restrictive clauses. "He is the man who led the party to victory." "War Admiral was a race horse who received international acclaim." "This rug, which is a 16th century Ispahan, is very rare and costly." ("Which is a 16th century Ispahan" is nonrestrictive). "The books that I have recommended may be found on the shelves of the school library." ("That I have recommended" is restrictive.)
Wire. Colloquial for telegraph.
Without. Do not use as a conjunction for except or unless. Without introduces a phrase; except and unless introduce clauses. "It is unlawful to operate an automobile unless (NOT without) you have a license," or "It is unlawful to operate an automobile without a license."
Would have. Frequently misused for had. "If he had (NOT would have) studied, he could have passed the examination."
Yourself. An emphatic or reflexive pronoun. Do not use incorrectly in place of you.
You was. Never! Always you were, or were you, or weren't you, or you weren't.