monomials are one piece, like 7y. Binomials are two, hence "bi".these look like this (x - 7) for example. trinomials are three, hence the "tri". For example (2t² + 4t - 8). And then there are polynomials, poly stands for many. An example of a polynomial would be (t² + 4t³y - 2ty + 12y³). I hope this helps! I am currently working on this so it is fresh and easy.