It was only when I fully understood the poem to appreciate its beauty.
A. did I e
B. then I came
C. had I e
D. that I came
网友回答
A. did I e
B. then I came
C. had I e
(答案→)D. that I came
解析：考查强调句型。本题是强调句型，强调句型的基本结构为It is/was被强调成分that/who其它成分；其最大的特点就是去掉it is/was…that/who…句子仍然成立。要注意强调句型能强调除谓语动词以为的所有的句子成分。在考查的时候，经常会把强调句型和定语从句结合在一起考查，要注意分析句子的成分。本句强调的是时间状语从句only when I fully understood the poem。要特别注意强调句型使用陈述语序。故D正确。