Joan saw her boyfriend off at the railway station. She waved until the train was .
A. in sight
B. out of sight
C. at first sight
D. lost sight
网友回答
A. in sight
(答案→)B. out of sight
C. at first sight
D. lost sight
解析：考查词组辨析：A. in sight在视野内，B. out of sight看不见，C. at first sight第一眼 D. lost sight失明，句意是：琼到火车站给她的男朋友送行，她挥手告别直到火车消失在视野之外。选B。