－How did you find those days.
－The days we spent together on the farm are not easy ．
A. that；to forget
B. when；to be forgotten
C. when；to forget
D. that；to be forgotten
网友回答
(答案→)A. that；to forget
B. when；to be forgotten
C. when；to forget
D. that；to be forgotten
解析：A 考查定语从句及固定句式。that代替先行词the days在定语从句中作spent的宾语。“be ＋adj.＋to do”结构中通常用主动形式。