What Is the Difference Between Comprise and Compose?

Consider the definitions of the words comprise and compose, two words that are commonly confused with one another. This will provide you with a foundation of what each word means on its own so you can use them correctly.

• Comprise is a verb that means "to contain." The word is used near the beginning of a sentence.
  Example: The house comprises ten rooms and three baths.
• Compose is a verb that means "to combine,” “to put something in order,” or “to make up." The word is used near the end of a sentence.
  Example: Ten rooms and three baths compose the house.

Now that you know the definition of the word comprise, the next step is to make sure you’re clear on how to use it properly. Mastering that skill requires understanding proper word usage and developing the ability to recognize improper usage.

Comprise, in its simplest form, means “to contain.” For example, you could correctly say, "The farm comprises ten cows, three horses, five sheep, and four pigs." This is just like saying, "The farm contains ten cows, three horses, five sheep, and four pigs."

It would be incorrect if you said "Ten cows, three horses, five sheep, and four pigs comprise the farm." If you are using the word comprise, the whole must come first. The whole, which in this case is the farm, must come earlier in the sentence than the parts, which are the cows, horses, sheep, and pigs.

Review the following statements that indicate correct and incorrect usage of the word comprise. Make sure you understand the rationale.

The class comprises 16 boys and 12 girls. (correct)

In the correct answer, you could substitute the word contains for comprises and the sentence would still be correct. This is not the case with the incorrect answer. Since the word comprise means “to contain,” the option where the word’s definition could be substituted is the one that is right.

A total of 16 boys and 12 girls comprise the class. (incorrect)

The class is the whole and the students are the parts. Therefore, in order for comprise to be used, the whole (the class) needs to appear earlier in the sentence than the students, which are the parts.

Now that you’re clear on how to properly use comprise, the next step is to learn when to use the word compose. The word compose means "to make up or combine." While this word is similar to the word comprise, it has this distinct meaning.

The incorrect option listed in the comprise usage section illustrates situations where compose would be the correct word to choose.

A total of 16 boys and 12 girls compose the class. (correct)

Compose is the correct word because the definition “make up” could correctly be substituted for compose. The other indicator that compose is the right word to use in this context is the fact that the part (16 boys and 12 girls) comes before the whole (the class).

It is incorrect to use compose and comprise interchangeably. While not unrelated to each other, these words do not have the same meaning. If you use compose in a sentence that should really contain the word comprise, then there is an error in the sentence.

The class composes 16 boys and 12 girls. (incorrect)

As previously mentioned, the word comprises would be the correct term in a sentence structured like this one. The word contains could correctly be substituted for comprises in this word grouping, while none of the definitions of compose would fit. For compose to be the correct choice, the whole (class) would have to come after the part (16 boys and 12 girls).

Review the following statements that indicate correct and incorrect usage of the word compose.

A mixture of eggs, flour, butter, milk, and sugar compose a cake. (correct)

The phrase “make up,” which is a definition of compose, could be substituted for the word compose in the sentence. The parts (eggs, flour, butter, etc.) come before the whole (cake) in the sentence.

A mixture of eggs, flour, butter, and milk comprise a cake. (incorrect)

Basically, the words comprise and compose are used in opposite situations. Their meanings are similar, but in a sense, they are opposites in terms of how they are used.

• Compose (to contain) is used when the part comes before the whole.
• Comprise (to combine or make up) is used when whole comes before the part.

Choose the correct word for each example below. Don’t peek ahead at the answers until after you’ve attempted all of the items yourself.

Select the correct word for each of the following statements.

1. The orchestra (comprises / composes ) brass, woodwind, percussion, and string instruments.
2. Multiple choice, fill-in-the-blank and true/false questions (compose / comprise) the final exam.
3. My ideal garden (comprises / composes) leafy greens, tomatoes, cucumbers, and okra.
4. Going to parks, museums and caves (comprises / composes ) my perfect vacation.
5. My ideal date (comprises / composes ) a gourmet meal and a moonlit walk on the beach.

The correct answers are as follows:

1. comprises
2. compose
3. comprises
4. composes
5. comprises

Another important consideration related to how these words should be used is related to the phrases "is composed of" and "is comprised of."

• Many grammar guides actually suggest that the phrase "is comprised of" is always incorrect. When you think about it, it makes sense. It does not make sense to say "is contained of," but it does make sense to say "is made up of."
• However, the phrase "is comprised of" is often used and is growing in popularity with grammar experts. For example, some experts consider it correct to say "The farm is comprised of ten cows, three horses, five sheep, and four pigs." and "The class is comprised of 16 boys and 12 girls."

This is a good example of how language is always evolving. If, however, you want to be certain that no one will wonder if you might be misusing a word, it’s best to avoid using “is comprised of,” at least until such time that it becomes universally accepted.

Proper word usage is critical in writing. Whether your writing is limited to school assignments, you have a job that requires writing or you engage in creative writing as a hobby or profession, the more you learn about how to choose the correct words, the better your writing will be. Spend some time learning how to choose between other words that are often confused, such as further vs. farther. If you find spelling to be more challenging that word selection, review some of the most commonly misspelled words in the English language.