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 denote 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.
(This is one of the areas under debate. Many advocate that 'comprise' cannot be
used to denote that the smaller parts make up the whole. They believe this is
when 'compose' should be used. If you adhere to this ruling too, you will
never be wrong.)
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'
(note: it correctly includes the word 'of') is considered by many to be non-standard English. To avoid criticism, reword your sentence to avoid this
construction.
Examples:
The water
molecule is comprised of two atoms of hydrogen and one atom of oxygen.
(Contentious version. Some of your readers may frown at this version.)
The water
molecule comprises two atoms of hydrogen and one atom of
oxygen.
(Reworded, non-contentious version)
Compose
'To compose' means 'to make up' or 'to make'.
It is used to denote that 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'
(note: 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.
Select the correct version:
|
|
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.
(Our solar system also includes the Sun, an asteroid belt
and a number of dwarf planets. Therefore, compose is incorrect in this
example.)
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.
|
|
Common grammar errors
