Most parents encourage their children to take an active part in social events, those events do not interfere with their studies.
A. concerning
B. until
C. unless
D. provided
网友回答
A. concerning
B. until
C. unless
(答案→)D. provided
解析：词义辨析题。A. concerning 关于 B. until 直到 C. unless 除非 D. provided 只要 大多数父母允许孩子参加参加社会活动只要这些活动不影响学习。 根据语境选D