题目：Please take a ticket and proceed to the service counter after your
mumber____.
(A) was called
(B) will be called
(C) has been called
(D) will call
疑问：小弟时态很弱，先谢谢各位大大为我解答。
答案是第三个，想问为什么不是第一个。感很第一个很满适合的。

"after"在此是连接词，其所起的子句动作尚未实现，是祈始句的先决条件，不能用过去式，只能用现在式was called (X), is called/ have been called 后者强调完成 (O)另举例 e.g.: Please turn in your weekly journalto the instructor after you proofread/ have proofread it.