Question

passive of "Sit down"

Answer 1

"Sit down" is an imperative sentence that expresses a request. The sentence an also be written as "Please sit down" . In case of requests, to convert an active sentence into a passive sentence- "You are requested" or "You are advised" is ought to be used before the sentence.
Passive voice- "You are requested to sit down."
                                        OR
                          "You are advised to sit down."

Answer 2

Hay mate here is your answer ✌❤☺


You are ordered to sit down.

or - You are requested to sit down.

Hope it will help you ☺❤