Leveraging our knowledge

There are a number of ways we can work out things we either never knew, or have forgotten, from things we remember.

I propose to deal with this by giving examples, and then trying to classify them.

Suppose I cannot remember what to call an event which happens every two years. I can think of common prefixes which seem to denote two: bipedal and biplane, duopoly and duality,

With the help of this I can dredge from my memory a couple of possibilities: biannual and biennial. I also remember that one of these means twice a year, and the other means once every two years.

This is where I have several options: I can try and figure ...