A:一般
B:等腰
C:等边
D:直角
A. It's time for Chinese class. B. It's time for lunch.
C. It's time for school. D. Time to go home.
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李老师去年到欧洲进行了短期交流学习。据此回答有些问题。
为后来北宋结束分裂割据的局面准备了重要条件的是( )