A. them B. those C. that D. who
A. will they B. they will C. have they D. they have
A. that we don't know B. what we don't know C. unknown D. what unknown
A. when B. that C. which D. how
A. during which B. that C. while D. when
A. did B. had C. would D. when
A. until, that the boy was sent B. until, did that boy get sent C. not until, that the boy was sent D. not until, did that boy get sent
A. it is when that B. when it is that C. that when it is D. when is it that
A. because, that B. that, that C. because, which D. /, that
A. had B. did C. would D. when
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