An unexpected gust （）on us last night.

His sense of （）stopped him from leaving the post.

A.responsibility
B.duty
C.obligation
D.promise

点击查看答案&解析

I showed him the pictures I （）of the animals the day before，and told him the stories.

A.was taking
B.had taken
C.have taken
D.was taken

点击查看答案&解析