وَصَلَ الضَّيْفُ صَبَاحًا
The guest arrived in the morning.
جَلَسَ الطَّالِبُ فِي الْمَكْتَبَةِ
The student sat in the library.
Temporal and spatial adjuncts indicate when and where a reported event occurred. They are especially valuable when a listener must distinguish among several possible times or locations.
Such qualification does not universally exclude every other occurrence. “He arrived in the morning” is not equivalent to “he has never arrived at any other time.”