We may not separate terumah by measure, nor by weight nor by count; but one may separate terumah from that which is measured, from that which is weighed and from that which is counted.  We may not separate terumah with a basket or a container of [known] measure; but one may use them to separate terumah using half [their volume] or a third [of their vol-ume]. One may not separate terumah using half [the volume of] a se'ah container, for half [a se'ah container] is a [precise] measure.