Phrasal verbs change meaning with each particle. Which means 'to remove'? 'Please ___ your shoes before entering.'

"Take off" means to remove something, and it comes from the physical image of lifting an item away from your body — a coat, a hat, or shoes. English phrasal verbs work this way constantly: the base verb (take) stays put, but the particle (off, on, up) reroutes the meaning entirely, almost like a different word attached to the same root.

"Take on" means to accept a responsibility or challenge, as in taking on a new project. "Take up" means to begin a hobby or occupy space or time, as in taking up painting. None of these overlap with removing an object, which is why only "take off" fits the shoe sentence.

The same particle system explains why "take off" can also mean a plane leaving the ground — the shoe stays on the floor, but the image of something separating and lifting away is the same logic reused in aviation.