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23. Every Monday morning, all the teachers and students in our school stand at ____ as our national flag is raised.

23. Every Monday morning, all the teachers and students in our school stand at ____ as our national flag is raised.

A. attention                B. attentions                 C. at ease                      D. Attentively

Every Monday morning, all the teachers and students in our school stand at ____ as our national flag is raised.

A. attention　 B. attentions　 C. at ease　 D. attentively