Good question. So many native speakers get this wrong. Comprise means 'contains', 'made up of'. You use it to identify the constituent parts of a whole. The property comprises four main buildings. The course comprises six face to face lectures and regular tutorials conducted by video conferencing. Compose refers to the elements which combine to make a whole. Equal parts rum, lime juice and syrup compose the drink. This can also be expressed as 'the drink is composed of equal parts rum, lime juice and syrup' . So you can say that a larger thing 'comprises', or 'is composed of' smaller things. So to summarise: a big thing comprises (contains) several smaller things A big thing is composed of (made of) several smaller things What you can NEVER say (yet I see and hear this often), is 'comprised of'. Nothing is ever comprised of anything

unlike comprise, compose means to make up basically these two words are the opposite of one another.compose is used when the part comes before the whole, and comprise is used when the part comes before the whole

nyc question