Comprise or Compose?
Comprise or Compose?
What is the difference between "comprise" and "compose"?- "To comprise" means "to consist of."
- The cake comprises four slices.
- "To compose" means "to make up."
- Four slices compose the cake.
Comprised or Comprised Of?
Here are three common issues related to "comprise":- (1) Do not use "of" with "comprise."
- The play comprises of three parts.
- The play comprises three parts.
- (2) Avoid the construction "is comprised of."
- The play is comprised of three parts.
- Avoid naming the constituent parts first.
- Three parts comprise the play.


More about "Comprise" and "Compose"
There is often confusion over "comprise" and "compose." The situation is not helped by ongoing debate about how to use "comprise." If you stick to the guidelines below, you will be on safe ground.Comprise
"To comprise" means "to consist of" or "to be made up of." It is used to state that something "is made up of" smaller parts. Do not use the word "of" with comprise.Examples:
- The water molecule comprises two atoms of hydrogen and one atom of
oxygen.
(The whole comprises the smaller parts.)
- The water molecule comprises of two atoms of hydrogen and one atom of
oxygen.
(Do not use the word "of" with "comprise.")
- Two atoms of hydrogen and one atom of oxygen comprise the water molecule.
- The three wise monkeys comprise Mizaru (see no evil), Kikazaru (hear no evil), and Iwazaru (speak no evil).
- The quadriceps femoris comprise the rectus femoris, the vastus medialis, the vastus intermedius, and the vastus lateralis.
Is Comprised Of
The construction "is comprised of" (it correctly includes the word "of") is considered by many to be non-standard English. To avert criticism, reword your sentence to avoid this construction.Examples:
- The water molecule is comprised of two atoms of hydrogen and one atom of oxygen.
- The water molecule comprises two atoms of hydrogen and one atom of oxygen.
Compose
"To compose" means "to make up" or "to make." It is used to state that smaller parts make up the whole (i.e., the opposite of comprise). Do not use the word "of" with compose.Examples:
- Mercury, Venus, Earth, and Mars compose the inner planets.
- The rectus femoris, the vastus medialis, the vastus intermedius, and the vastus lateralis compose the quadriceps femoris.
- Two atoms of hydrogen and one atom of oxygen compose the water molecule.
Is Composed Of
The construction "is composed of" (it correctly includes the word "of") does not attract the same criticism as "is comprised of."Examples:
- USA is composed of 50 states.
- The water molecule is composed of two atoms of hydrogen and one atom of oxygen.
Name All the Constituent Parts
Make sure you name all the constituent parts when using "comprise" or "compose."- Since August 2006 when the International Astronomical Union declassified Pluto as a planet, only eight planets compose our solar system.
Beware "Include"
Do not name all the constituent parts when using "include."- The water molecule includes two atoms of hydrogen and one atom of oxygen.
- The water molecule includes one atom of oxygen.
Interactive Exercise
Here are three randomly selected questions from a larger exercise, which can be edited, printed to create an exercise worksheet, or sent via email to friends or students.- Do you disagree with something on this page?
- Did you spot a typo?