I will never forget that terrible accident it happened so long ago.
A. even though
B. so that
C. only when
D. ever since
网友回答
(答案→)A. even though
B. so that
C. only when
D. ever since
解析：
此题考查的是让步状语从句，用even though来引导，全句意为：我永远也不会忘记那发生在很久之前的可怕的事故。So that引导原因状语从句，only when只有当；除非，ever since自从，不合题意，选A。