The days we spent together on the farm are not easy ．
A. when,toforget
B. which, to be forgotten
C. that, to forget
D. /,to be forgotten
网友回答
A. when,toforget
B. which, to be forgotten
(答案→)C. that, to forget
D. /,to be forgotten
解析：第一空考查定语从句先行词The days关系词在从句中做宾语要用that\which\不填。第二空sth be easy to do 用主动结构表达被动含义。句意：我们一起在农场度过的日子不容易忘记。