There is a return stroke after the lightning hits the ground.

在闪电击向地面以后出现了一次回击。

There are some differences for the mean of return stroke currents in different regions.

不同地区地闪回击电流平均值略有不同。

Eventually a negative stepped leader travels downward and reaches the ground, creating a return stroke.

最终一个下行传播的负极梯形先导接触到地面，制造了一次回击。

The bright return stroke travels upward at around half the speed of light, and is too fast to capture in more than one image.

闪亮的回击以光速的一半速度上行传播，由于它的速度太快，在一张图象中不能捕捉到这一过程。

This upward leader connects with the downward leader and a return stroke occurs. Five more dart leader-return strokes follow.

上行先导与下行先导连接，于是产生了一次回击，随后又是五次以上的直窜先导型回击。