When particular phonemes occur next each other (e.g. English /sp/ in /spin/), while others do not (e.g. /sb/), we will say that the phonemes which occur next to each other all have some one component in common. The length of a component will therefore always be an integral number of phoneme-lengths—1, 2, 3, etc.—but need not be just one. - Harris (1944), a pag.188