Presupposition Triggers

A presupposition is a background belief or assumption that a speaker makes before they construct a sentence. It is the information the speaker assumes the listener already knows and accepts as true. To analyze presuppositions, linguists look for "triggers," which are specific grammatical structures or vocabulary words that act as red flags, signaling that a hidden assumption is embedded in the sentence.

There are several vital categories of triggers.
Factive verbs are verbs like realize, know, or regret. If someone says, "She regrets failing the exam," the verb 'regrets' triggers the unavoidable assumption that she actually failed the exam.
Change of state verbs include words like stop, start, or continue. If a police officer asks a suspect, "When did you stop stealing cars?", the word 'stop' traps the suspect by triggering the assumption that they used to steal cars in the past. Finally,
Iteratives are words like again, anymore, or another. Saying, "The teacher is late again," triggers the assumption that the teacher was late at least once before.