A curved line segment consists of two data points (endpoints) and two control points (handles). A control line connects a control point to a data point. You can change the shape of a curve by converting a data point to a different type, or by dragging the control points to a different location.
曲线段含有两个数据点（端点）和两个控制点（控点）。控制线将控制点和数据点连接起来。您可以通过转换数据点的类型或者将控制点拖到其他位置，来修改曲线的形状。