The example he used was “Time flies like an arrow.” The sentence might mean that time moves with the swiftness of an arrow swooping through the sky. But as Oettinger explained, “time” could also be an imperative verb—a stern instruction to an insect-speed researcher “to take out his stopwatch and time flies with great dispatch, or like an arrow.” Or it could be describing a certain species of flying bug—time flies—that exhibit a fondness for arrows.
