Final answer:
The phrase "shortly after eight o'clock" is the temporal transition, as it indicates the timing of an event in the narrative.
Step-by-step explanation:
The temporal transition among the bolded phrases provided is "shortly after eight o'clock". Temporal transitions are words or phrases that provide a time reference, helping to sequence events in a narrative. The phrase "shortly after eight o'clock" clearly indicates the timing of an event, which is essential for understanding the sequence and pacing of the story's action.