So here is the problem I met:
I start from step 1, then after clicking "insert" in step 2, it ended up at step 3. And no matter how many times I repeat, it stays at step 3...
Any clue for that?
PS: 叮噹 is really warm-hearted, I am wondering maybe he is the boss of this website? lol. If not, thank you for all XD.