The traditional rule
The traditional distinction is elegant: the whole comprises the parts, and the parts compose the whole. "The committee comprises twelve members" means the committee contains or includes all twelve. "Twelve members compose the committee" means the members make up the whole.
A useful restatement: "comprise" means "to contain" or "to embrace all of." If you can swap in "contains," you are using "comprise" correctly. "The album comprises ten tracks" works because "The album contains ten tracks" works.
The "comprised of" debate
"Comprised of" is one of the most hotly contested phrases in English usage. Purists consider it always wrong because "comprise" already means "to be made up of," making "comprised of" redundant, like saying "is included of." Descriptivists point out that "comprised of" has been in common use for over a century and appears in reputable publications.
The practical advice: avoid "comprised of" in formal, edited writing. It will be flagged by careful editors and may distract knowledgeable readers. Use "composed of," "consisting of," "made up of," or simply restructure with "comprises." In casual writing, the phrase is widely understood and unlikely to cause confusion.
- Correct: The jury comprises twelve citizens.
- Correct: The jury is composed of twelve citizens.
- Correct: Twelve citizens compose the jury.
- Disputed: The jury is comprised of twelve citizens.
- Alternative: The jury consists of twelve citizens.
Safe alternatives when in doubt
If the comprise/compose distinction feels slippery, sidestep it entirely. "Consists of," "is made up of," "includes," and "contains" all work in most contexts and never trigger editorial objections. Choosing a simpler synonym is not a sign of weakness, it is a sign of a writer who prioritizes clarity over showing off vocabulary.
Quick editing check
When you encounter "comprise" in your own writing, apply the substitution test. Replace it with "contains" or "includes." If the sentence still makes sense, your usage is correct. If you wrote "is comprised of," replace the entire phrase with "consists of" or "is composed of" to stay on safe ground. This two-second test catches the most common errors without requiring you to memorize the full grammatical analysis.