Tells the listener to break off an action already in progress; 再 adds "any more," 了 marks the turn to the new state.
框 · Frame
別（再）[verb (phrase)] 了！
觸 · Trigger
Someone is already doing something and you want them to break off and stop now.
序 · The move
1name the action already running that you want stoppedis it something in progress, not something never started?
2set 別 in front of that verb to bar itis this aimed at the listener, not your own plan?
3drop 再 in after 別 for "any more," and close with 了 at the enddoes 了 land at the sentence end marking the turn, not on the verb as a completion suffix?
例 · Examples
1別don't (bars the action)再any more (one further round)說話talk / speak了marks the turn to the new state，比賽要開始囉！
Bare 別 + verb forbids an action outright (別說話 — don't talk, whether or not it has begun). 別（再）…了 specifically breaks off an action already running: 再 says "no more rounds," 了 marks the turn. Forbidding versus halting.
（請）不要 is the full, polite-capable bar; 別 is that same 不要 fused into one blunt syllable. The 再…了 brackets add the "stop what's ongoing" reading to either.
Sentence-final 了 alone reports a change has happened (下雨了 — it's raining now). Inside 別…了 the same 了 demands a change be made — the turn is ordered, not observed.
了 placed on the verb as a completion suffix: 別再說了話 → 別再說話了（了 closes the sentence at the end）
再 dropped when halting an ongoing action: 別說話了 reads as a blunt cut; 別再說話了 names the "any more" the speaker means
object after 別 with no verb: 別話了 → 別說話了（別 bars a verb, not a noun）
English "stop talking / don't talk any more" puts the continuation in the verb ("stop", "any more"); learners leave out 再 or 了 and produce a flat 別說話, losing the "break off what's running" reading.