We may not designate terumah from leket, from shich'chah, from pe'ah, or from ownerless [produce]; nor from maaser rishon whose terumah was [already] taken; nor from maaser sheni and consecrated produce that were re-deemed; nor from that which is obligated [in tithing] on behalf of that which is exempt [from tithing], or from that which is exempt on behalf of that which is obligated; nor from that which is detached [from the ground] on behalf of that which is attached, or from that which is attached on behalf of that which is detached; nor from the new [crop] on behalf of the old [crop], or from the old [crop] on behalf of the new [crop]; nor from produce of the Land [of Israel] on behalf of produce from outside the Land, or from pro-duce from outside the Land on behalf of produce of the Land. If they designated terumah [thus], their terumah is not terumah.