What are the subunits called that make up carbohydrates?

You can have 3.

Monosaccharides - meaning 1 sugar

Disaccharides - meaning 2 sugars

And Polysaccharides - meaning many sugars (example-glucose)

A monomer is a small molecular subunit that can be combined with similar subunit to form larger molecules. In living systems, like our own bodies, these larger molecules include carbohydrates, lipids, nucleic acids and proteins. The monomers of these organic groups are carbohydrates.