elliptic parallel

例句：

1. 1. The ellipse is the curve that divides aplane into two equal halves.
   椭圆是把平面分成两个相等部分的曲线。
2. 2.The parabola is the curve thatdescribes the path of an object moving ina straight line.
   抛物线是描述物体沿直线运动轨迹的曲线。
3. 3. Theellipse and parabola areboth curves that can be used to describethe shape of objects.
   椭圆和抛物线都是可以用来描述物体形状的曲线。