They talked for about an hour about the things and the persons they remembered in the scho

问题补充：

They talked for about an hour about the things and the persons they remembered in the school.

A. which

B. that

C. who

D. whom

答案：

A. which

(答案→)B. that

C. who

D. whom

解析：考查定语从句。句中先行词为things and the persons，即指人也指物，在从句中作宾语，故只能用关系代词that，选B。