The phrasal verb "keep off" is more commonly used in informal speech and writing, though it can occasionally appear in formal contexts, particularly when clear and direct instructions are necessary, such as in signage or official health warnings. Generally, "keep off" is employed to advise or instruct someone to stay away from a particular place, surface, or activity. It can be used imperatively, as in instructions like "Keep off the grass," or as advice, such as when suggesting someone maintain distance from a contentious topic: "I’d keep off politics if I were you." Furthermore, it can also denote the action of refraining or abstaining from something, such as in diets or habits: "He was advised to keep off sugar." This phrasal verb often connotes physical or metaphorical distancing to prevent potential harm, damage, or conflict.
B1
PreIntermediate
1. To avoid stepping on or touching something.
Please keep off the grass to allow it to grow.
The sign warned hikers to keep off the fragile dunes.
2. To stay away from something, especially to avoid causing harm or damage.
After his illness, the doctor advised him to keep off oily foods.
It's a private property, so the notice tells you to keep off the premises.
3. To prevent something from being discussed or prevent an action.
Let's keep off the topic of politics during dinner.
He's trying to keep off any discussion about his future plans.