Comprise: consist of, be made up of
Compose: write or create
These are two of the most commonly misused words in the English language. Comprise means to include; compose means to make up.
It all comes down to parts versus the whole. When you use comprise, you put the whole first: “A soccer game comprises (includes) two halves.” When you use compose, you put the pieces first: “Fifty states compose (make up) the United States of America.”