Sentence:  The highway to the East Coast which ran through the borough of Ebbfield had always been a main road and even now, despite the vast garages, the pylons and the gaily painted factory glasshouses which had sprung up beside it, there still remained an <WSD>occasional</WSD> trace of past cultures. 
Meaning of the word marked with <WSD> tags:  Occurring or appearing irregularly from time to time, but not often.