Insert, overwrite shortcut keys

Step-by-step progressive teaching: The existing editing training videos on the market either have too many nonsense lecturers; or the operation is stagnant, the waiting time is too long, and life is wasted; or the excessive pursuit of short videos, the content is within one minute, Showing for the sake of showing, only suitable for advanced editors to review, not suitable for beginners to learn. And our course content is compact and practical, helping learners to sort out the editing concept and operation concept again and again. Really formed editor ideology.