Every Monday morning, students in our school would stand at attention, watching the national flag .
A. raising
B. rising
C. being risen
D. being raised
网友回答
A. raising
B. rising
C. being risen
D. being raised
解析：考查非谓语动词。“升旗”raise a flag，旗帜是被升起所以用现在分词的被动式。句意为：每天早晨我们学校的学生立正看国旗升起。