Jamieson, Fausset and Brown on 1 Corinthians 10:17

17. one bread--rather, "loaf." One loaf alone seems to have been used in each celebration.

and one body--Omit "and"; "one loaf [that is], one body." "We, the many (namely, believers assembled; so the Greek), are one bread (by our partaking of the same loaf, which becomes assimilated to the substance of all our bodies; and so we become), one body" (with Christ, and so with one another).

we ... all--Greek, "the whole of us."