15 The construction has: “[The] lamb … will be to you.” This may be interpreted as a possessive use of the lamed, meaning, “[the] lamb … you have” (your lamb) for the Passover. In the context instructing the people to take an animal for this festival, the idea is that the one they select, their animal, must meet these qualifications.
16 The Hebrew word תָּמִים (tamim) means “perfect” or “whole” or “complete” in the sense of not having blemishes and diseases—no physical defects. The rules for sacrificial animals applied here (see Lev 22:19–21; Deut 17:1).
17 The idiom says “a son of a year” (בֶּן־שָׁנָה, ben shanah), meaning a “yearling” or “one year old” (see §128.v).
18 Because a choice is being given in this last clause, the imperfect tense nuance of permission should be used. They must have a perfect animal, but it may be a sheep or a goat. The verb’s object “it” is supplied from the context.

In other versions

Your lamb shall be without blemish, a male a year old. You may take it from the sheep or from the goats,

The animals you choose must be year-old males without defect, and you may take them from the sheep or the goats.

You must have an unblemished animal, a year-old male; you may take it from either the sheep or the goats.

The animal you select must be a one-year-old male, either a sheep or a goat, with no defects.

The lamb for you must be a male, without defect, in its first year; you will take it from the sheep or from the goats.

Your lamb shall be without blemish, a male of the first year: ye shall take it out from the sheep, or from the goats:

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