Well, it could be that the words reveal a secret that powerful forces don't want known, and so speaking them leads to death as a punishment. Or they might be part of a forbidden language that has dire consequences when uttered.
Maybe those words are like a code or trigger that activates some sort of deadly curse or magic. It's a common plot device in fantasy novels.
Sometimes, in novels, certain words spoken mean death because they are tied to an ancient prophecy or a dark pact. The characters unknowingly invoke a fatal outcome when they say those specific words.
Chapter 795, "Trouble Befalls the Third Lady!", is the clearest early answer because it turns Jiang Mingchuan's situation into a concrete plot event. The chapter turns that into something concrete by moving from The group photo was spreading like wildfire on Weibo.
Chapter 503, "How could they let an actor marry in?", is the clearest early answer because it turns Xueding Longjing's situation into a concrete plot event. A useful checkpoint is the way the scene starts with The servants standing outside the gilded mahogany gateway were all...
Chapter 643, "Jiang Li Dominates the Trending Searches!", is the clearest early answer because it turns Round Brain's situation into a concrete plot event. Early on, Qi Tianyu joyously carried his construction to the side to wait for....
Chapter 557, "Where Did This Rotten Fish Come From, It's Disgusting", is the clearest early answer because it turns Shang Shuyue's situation into a concrete plot event. Early on, The triple broth was almost done, Jiang Li dusted her hands off and....
A practical answer is Chapter 3, because it turns the idea into a concrete scene. The chapter opens with Qiao was still annoyed at the attitude of this unknown girl when she heard..., adds pressure through So without a second thought, she blurted out a fierce challenge, "Fine, if..., and ends on.
Chapter 589, "Green Tea! Green Tea! Damn Green Tea!", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event. Early on, Thinking of this, Zhao Lang gave a slight smile, "Alright, pedaling....
Chapter 869, "This Marriage Must Not Happen!", is the clearest early answer because a shaky connection becomes usable in the plot. A useful checkpoint is the way the scene starts with Xue Wandeng also liked this daughter-in-law very much and hurriedly...
Chapter 598, "She Blew Up Your Family's Lake!", is the clearest early answer because it turns Gu Shengrong's situation into a concrete plot event. It opens with Have you all fallen silent?] [I've fallen silent as well.] [Some say...
Chapter 738, "Here to Fight!", is the clearest early answer because the buildup finally cashes out in a real clash. The chapter gives readers a real answer by opening on Feeling that something was amiss, he immediately called Jiang Li.
Chapter 530, "I Only Drink 80 Degree Tea!", is the clearest early answer because it turns Zhou Xu's situation into a concrete plot event. The chapter turns that into something concrete by moving from Old Sir Gu took a step back, his expression cold and guarded as he...