Situation: A student doubts a report about a trip. The teacher says إِنَّ الرَّحْلَةَ غَدًا
The trip is indeed tomorrow.
Inna emphasizes the assertion in response to doubt. With a listener already convinced, al-riḥlatu ghadan might suffice. Ghadan identifies the time; al-riḥlah points to an identifiable trip.
The analysis combines declarative speech, emphasis, definiteness and temporal qualification. Each label must be tied to an observable feature rather than merely listed.