It was only when I read his poems again recently I began to appreciate their beauty.
A. until
B. then
C. that
D. so
网友回答
A. until
B. then
(答案→)C. that
D. so
解析：句意：就是只在我最近又看了一遍他的诗时我才开始欣赏它们的美。It is/was ... that...是强调句式。在这里强调时间状语。that不能用其他词代替。所以选C。
考点: 考查强调句式的用法。