问题补充：
---I phoned you at six yesterday afternoon, but nobody answered.
----I a walk with my parents near the river.
A. am taking
B. was taking
C. took
D. will take
答案：
A. am taking
(答案→)B. was taking
C. took
D. will take
解析：
试题分析: 句意：昨晚六点我打电话给你，但无人接听。我正在河边和我父母散步。take a walk散步。根据at six yesterday afternoon昨晚六点，可知是过去进行时，故选B.
