parabolic metric geometry

例句：

1. 1. The parabola is the shape of a curve that has its vertex at the center and opens upwards.
   抛物线是具有顶点在中心且开口向上的曲线形状。
2. 2. In physics, a parabola represents the path of an object moving along a straight line with constant acceleration.
   物理学中，抛物线代表物体沿直线匀加速运动时的运动轨迹。
3. 3. The parabola is used to describe the path of a projectile when it is thrown horizontally.
   抛物线用于描述当弹丸水平抛出时的轨迹。