The（）action of the policemen saved the people in the house from being burnt.

单项选择题All flights（）because of the storm, they decided to take the train.

A. having canceled
B. having been canceled
C. were canceled
D. have been canceled

单项选择题The association works to promote the （）of retired people as active and useful members of the community.

A. action
B. aspect
C. location
D. status