Oh, what a tangled web we weave when first we practice to conceive written communication. So many pairs or trios of words and phrases stymie us with their resemblance to each other. Here’s a quick guide to alleviate (or is it ameliorate?) your suffering:
1. a while / awhile: “A while” is a noun phrase; awhile is an adverb.
2. all together / altogether: All together now — “We will refrain from using that two-word phrase to end sentences like this one altogether.”
3. amend / emend: To amend is to change; to emend is to correct.
4. amount / number: Amount refers to a mass (“The amount saved is considerable”); number refers to a quantity (“The number of dollars saved is considerable”).
5. between / among: The distinction is not whether you refer to two people or things or to three or more; it’s whether you refer to one thing and another or to a collective or undefined number — “Walk among the trees,” but “Walk between two trees.”
6. biannual / biennial: Biannual means twice a year; biennial means once every two years.
7. bring / take: If it’s coming toward you, it’s being brought. If it’s headed away from you, it’s being taken.
8. compare to / compare with: “Comparing to” implies similarity alone; “compare with” implies contrast as well.
9. compliment / complement: To compliment is to praise; to complement is to complete.
10. comprise, consist of / compose, constitute: Comprise means “include,” so test by replacement — “is included of” is nonsense, and so is “is comprised of.” The whole comprises the parts or consists of the parts, but the parts compose or constitute the whole.
[Publetariat Editor’s note: also see Grammar Girl Mignon Fogarty’s take on comprise vs. compose, here]
11. connote / denote: To connote is to convey (“Air quotes connote skepticism or irony”); to denote is to specify (“A stop sign denotes the requirement to halt”).
12. continual / continuous: Continual events are frequently repeated, or intermittent. Continuous events are uninterrupted, or constant.
13. credible / credulous: To be credible is to be authoritative; to be credulous is to be gullible.
14. deserts / desserts: If you eat only cake, pie, ice cream, and the like, you eat just desserts. If you have it coming to you, you get your just deserts as well. (However, the connotation is negative, so hit the gym.)
15. different from / different than: The former phrase is preferred in formal writing; but “differently than” is always correct usage.