The answer must be revised. The student lost her/his book twice!
잃다 is lose/lost 잊어버리다 is forget/forgot The two are totally different
Isn't 잃(어버리)다 to lose? 잊(어버리)다 to forget? Some hints seem to have these as interchangeable. Or is the idea lose and forget actually interchangeable in korean ( like seek and find )
well, as they/their can be used to refer to a person of "unspecified gender" (as mentioned by the oxford dicitonary) it very well belongs here.
Doesn't it supposed to be "The student lost his book twice"?
For those quibbling about the gender neutral their being used, consider the word themself. You/you/your/yours is also plural, and the singular equivalent was thou/thee/thy/thine. So unless you want to go back to Shakespeare, Elizabethan English and such, I'd drop it.
It accepted my "lost" answer..
To those questioning about the "their", maybe the book belongs to some other people