e I, and (/^(c8) holds by Transfer, so cs = cl. Similarly for functions.

For all X, y e §, X Cs y x C1 y and x Us y = x U1 y\ cos = col; for all X e S, V s {x) = V l {x). So for standard sets there is no need to distinguish standard and internal versions of concepts. For nonstandard internal sets of course only the internal version makes sense.