题干
She used to in the morning，but now she is used to at night．
A：read，read
B：read，reading
C：reading，read
D：reading，reading
答案(点此获取答案解析）
B
She used to in the morning，but now she is used to at night．
A：read，read
B：read，reading
C：reading，read
D：reading，reading
，离心率
的椭圆两焦点为
，过
作直线交椭圆于
两点，则
的周长为（ ）
