Can anyone explain what “corollary” is? The lecture said, "through the lens of assumption, the stronger an argument is, the fewer and more reasonable its assumptions are. The corollary is that the weaker an argument is, the more and less reasonable its assumptions are."

#HELP

What makes "the only" (a sufficient condition indicator) function differently from "only" (a necessary condition indicator)? "The only" and "only" somehow seem literally equivalent to me.

Why isn’t “the cat likes milk.” which "drink" is a modifier of what cats want to do with the milk?