Definition: used to make a connection with an earlier statement Level: A2
我常坐的火车取消了。这就是我这么晚的原因。
My usual train was cancelled. ___That's why I'm so late.
她骗了他，那正是让他真正心烦的事。
She tricked him, and ___that's what really upset him.
我决定不再踢足球了。这就是我想卖掉它们的原因。
I decided not to play football any more. ___That is why I want to sell them.
