[If] one hires a laborer to work with olive trees, [and the laborer] said to him, “[I will work for you] on condition that I [may] eat olives,” [if] he eats one at a time, he is exempt [from tithes]; but if he combines [two or more olives], he is obligated [in tithes].  [If one hired a worker] to weed [a patch of] onions, [and] he said to him, “On condition that I [may] eat the green [leaves of the onion plant],” [the worker] may pluck one leaf at a time and eat [it without separating tithes]; but if he combines [two or more leaves], he is obligated [to tithe them].