People often describe something as being “comprised of” something else. This is normally seen as a mistake, since it’s using “comprise” in the passive voice to express the same meaning that it already expresses in the active voice.
The mansion is comprised of many rooms.
Living organisms are comprised of trillions of cells.
There are two ways to correct the error: use composed of instead, or use comprise(s) alone in the active voice.
The mansion is composed of many rooms.
Living organisms comprise trillions of cells.
It’s also wrong to use “comprise” in the active voice with the same meaning as “compose”—in other words, to say that the parts of something “comprise” the whole:
Individuals from various different backgrounds ______ the committee.
Academic books often ______ chapters written by different authors.
Sentences are ______ of words, which ______ individual letters.
An engine comprises a large number of components.
The whole (the engine) “comprises” the parts (the components), so you need the verb “comprise” here. “Comprises” is the third-person singular form of the verb, which is needed for subject-verb agreement with the singular noun “engine.”
The war was composed of several distinct stages.
You can tell that “composed” is needed here because a passive-voice phrasing with “of” is used. “Comprised of” would not be correct.
Individuals from various different backgrounds compose the committee.
Here, “compose” is used in the active voice. The parts (individuals) “compose” the whole (the committee).
Academic books often comprise chapters written by different authors.
The whole (the book) “comprises” the parts (the chapters). The plural form “comprise” is used here to match the plural noun “books.”
Sentences are composed of words, which comprise individual letters.
In the first part of this sentence, “composed” is needed to complete the passive phrasing “are composed of.” The second part uses “comprise” in the active voice instead.
People increasingly use “comprise” as interchangeably with “compose,” meaning that they consider words like “compose,” “constitute,” and “form” to be synonymous with “comprise.” However, this is still normally regarded as an error, and we advise against using these words interchangeably in academic writing.
Some synonyms and near synonyms of the verbcompose(meaning “to make up”) are:
People increasingly use “comprise” as a synonym of “compose.” However, this is normally still seen as a mistake, and we recommend avoiding it in your academic writing. “Comprise” traditionally means “to be made up of,” not “to make up.”
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Jack is a Brit based in Amsterdam, with an MA in comparative literature. He writes for Scribbr about his specialist topics: grammar, linguistics, citations, and plagiarism. In his spare time, he reads a lot of books.