A verb phrase with the subject dropped stands alone as a command aimed at the listener; 請 in front bows the order into a
框 · Frame
（請）[verb phrase]！
觸 · Trigger
You want the listener to do an action right now, plainly as an order or softened with 請.
序 · The move
1name the action you want done and lead with its verbdoes the verb start the utterance, with no subject in front?
2drop the subject — the listener is the one addressed and stays unspokenif you put 你 back in front, does it turn into a statement about the listener rather than an order?
3add 請 in front for a request, or leave it off for a flat orderdoes 請 sit at the very front of the whole VP, not inside it?
例 · Examples
1去洗手go wash hands (bare command)！來這裡排隊come line up here (bare command)！請小心開車please drive carefully (請 bows it)！保持安靜keep quiet (bare command)！
Go wash your hands! Come line up over here! Please drive carefully! Keep quiet!
去洗手 with no subject is an order handed to the listener; 你去洗手 with 你 in front reads as a statement about what you do or will do. Dropping the subject makes it a command; naming it describes the actor.
（請）不要 + VP (negative imperative)
Bare VP tells the listener to do the action (去洗手 — go wash up); （請）不要 + VP tells them to stop or hold it (不要說話 — don't talk). One hands over the deed, the other bars it.
subject left in for a command: 你去洗手 used to mean 'go wash your hands!' → 去洗手 (drop 你 for the order)
請 buried inside the VP: 小心請開車 → 請小心開車 (請 bows in front of the whole VP)
modal of wanting added: 請你要坐 → 請坐 / 請你坐 (the bare verb already carries the command)
English imperatives also drop 'you', so the bare VP transfers cleanly; the trap is 'please', which floats anywhere in English, while 請 only sits at the very front of the action being asked.