题干
—Sorry, Miss Liu. I forgot __________ my homework to school.
— __________ so careless, Sandy.
A：to bring; Don't be
B：to bring; Not be
C：bringing; Don't be
D：bringing; Not be
答案(点此获取答案解析）
A
-
＝1的两个焦点，点P在双曲线上，且满足∠F1PF2＝90°，则△F1PF2的面积是( )
配两片 
，这些可以配