"My teacher is teaching but I am not listening because I do not have an interest in history."
Translation:Tá mo mhúinteoir ag múineadh ach níl mé ag éisteacht mar níl suim agam sa stair.
In their broader meanings, spéis and suim are quite different. In the specific sense of being interested in something or finding something to be interesting, they are interchangeable. The English word "interest" has other meanings that are not translated as either spéis or suim.