题干
The government plans to bring in new laws _____ parents to take more responsibility for the education of their children.
A：forced
B：forcing
C：to be forced
D：having forced
答案(点此获取答案解析）
B
为直径两端点的圆，恰好过短轴的两顶点，则此椭圆的离心率
等于 （ ）