Language nuances.
There is no better way to truly understand them than to study abroad. To agree. To say yes. To acquiesce. To be in accord. To comply. To conform. To be in understanding. To consent. To reconcile. They all mean different, subtly but certainly different, things. And to think that I thought I knew how to say yes when I learned "oui."

To leave. To go home. In English they can have very similar meanings.
Partir. Quitter. Rentre. Retourner. In French, they're barely synonyms.

In my head, I'm siding with the French on this one. They are very very different emotions... I mean verbs?