Redundant ExpressionsHow to recognize and correct common redundant expressions
Conversational English is replete with expressions that are logically redundant but are still commonly used. Many of them are considered nonstandard, so look out for them:
actual fact (facts are by definition “actual”)
in close proximity to the building (proximity means “nearness”)
in proximity to the building
end result (a result is an end state by definition)
exact replica (a replica is usually an exact copy)
sufficient enough reason for his actions
sufficient reason for his actions
It’s generally best to streamline your writing by avoiding such redundancies. You might, however, choose to use some of these expressions for the sake of clarification or emphasis. When discussing a chain of causes and effects, for example, you might properly refer to the ultimate effect of these events as their “end result.” In addition, there are some redundant expressions that are accepted as standard idioms, such as “patently obvious” and “safe haven.” Distinguishing between the acceptable redundancies and the unacceptable ones is tricky—there are probably some grammarians who would argue, for example, that “close proximity” should fall into the former category.
Note that the writers of standardized tests like the SAT generally stay away from controversial linguistic territory, and they will probably only include errors that are widely recognized as errors by contemporary authorities.
Common Errors in English Usage: Errors in diction and idiom commonly made by native speakers of English
List of Common Errors in English Usage (PDF): Printable version of the complete list
Common Grammar Errors: A list of common errors in grammar (topics like subject-verb agreement and parallelism) as distinct from usage