sunglasses做主语时谓语动词用复数。如:Wherearemysunglasses?Theyareonthetable.类似的还有glasses,trousers,compasses,pants等,但是当用apairof/thispairof+这类词时,谓语动词用单数,如:Apairofcompassesisonthewriting-table.ThispairofglassesismadeinShanghai.