Well, if Sarah was in any way godly, what would the Bible say? That she gave her slave as a whore? (No, because the purpose wasn't sexual pleasure). That she gave her slave as a surrogate? (Oh, sure, I'm sure the Hebrews had a word for "surrogate" back then).
As my last post to you shows, the fact that Moses used the same word 9 chapters earlier to mean (sexual) "mate"--I think that's a possible translation...She gave her to be his (sexual) mate for the purpose of long-term pro-creation--exactly like the reason a female animal "mate" was secured onboard the ark in Gen. 7:2 was for purposes of long-term pro-creation. There's really no difference according to the promises of the rainbow covenant (for Noah's family & the animals in Gen. 7) or the promises of the Abrahamic covenant in Gen. 12 & what follows...both involved the long-term propagation of the species covenanted with God.
Abram could have refused and should have refused. (No disagreement there)
It is fairly clear that Hagar could have refused as well, since she apparently had the power to leave, which she later did after being mistreated by a jealous Sarai.
Um. This "power to leave"--is that the same kind of "power to leave" a runaway slave had as he used the underground railroad passage North?
Indeed it is a possible translation. However, I don't believe there is any legitimate translation that uses that word. But it is possible.
The fact is that Sarai was Abram's mate and so was Hagar. And that would be a legitmate translation provided that the same word was translated the same way both in the beginning of the sentence and the end. Since in that verse they are both described using the same word, the implication is that the relationship was deemed to be equal or identical.