3.As the years passed many occasions―birthdays awards graduations with Dad’s flowers.

问题补充：

3.As the years passed， many occasions―birthdays， awards， graduations with Dad’s flowers.

A. are marked

B. were marked

C. have marked

D. had marked

答案：

A. are marked

(答案→)B. were marked

C. have marked

D. had marked

解析：分析语境逻辑可知，该空表示“过去被标明”，因此应填一般过去时被动语态动词形式were marked。