What does Leviticus 14:50 mean?

and he shall kill one of the birds in an earthen vessel over running water:

And he shall kill the one of the birds in an earthen vessel over running water:

and he shall kill one of the birds in an earthen vessel over running water:

And put one of the birds to death in a vessel of earth over flowing water;

and he hath slaughtered the one bird upon an earthen vessel, over running water;

And having immolated one sparrow in an earthen vessel, over living waters,

and he shall kill one bird in an earthen vessel over running water;