mr green said he ( )in the school for about twenty years Aworked B works C is working D had worked说原因

mr green said he ( )in the school for about twenty years
Aworked B works C is working D had worked
说原因

D

这是相对said这一过去的动作来说的, 过去的过去, 所以用过去完成时

翻译： 格林先生说他在这所学校工作了大约20年之久

D had worked
for + time 标志着使用完成时

D had worked
过去完成时