More than a dozen students in that school abroad to study medicine last year.
A. sent
B. were sent
C. had sent
D. had been sent
网友回答
A. sent
(答案→)B. were sent
C. had sent
D. had been sent
解析：be sent abroad 表示“被派往国外”。有明确的过去时间状语last year，所以用一般过去时的被动形式。