Follow the LOS? Fixed Income difficulties

IMHO the fixed income part is the one that I’m finding the hardest, especially the beggining of the Study Session 14 (spot curves, forward, etc.)

The majority of the LOS in this SS states “Describe and understand…”. Should we take that literal? I mean, there is a huge difference between understanding the swap rate and being able to infer it from a 3 year period… So if we are expected to understand the concepts rather than calculate them, it’s gonna be a great relief. The same with the Z-spread, for example.