 Alternative ways of taking ‘a is red at t’ include treating ‘at t’ as an adverbial modifier, or as a sentential operator. According to the first ‘at t’, better written as ‘at t-ly’, is an adverbial modifier specifying the way in which something has a property. So ‘Plate is round at t1’ is true just in case Plate has roundness at-t1-ly. Plate, on this view, can be round at t1, but square at t2 because Plate can have roundness at t1-ly without having roundness at-t2-ly (See Johnston 1987, Haslanger 1989).