I owed an update yesterday, and I will make it up later today

In the middle of last night, a friend suddenly came from his hometown and had to be entertained. As a result, he was pulled away and played all night, and the loser was almost as trousers. Now I just got home with great sadness. I'm too sleepy to go to sleep first. Yesterday, I agreed with the editor that I would update a chapter and the result is owed. I promise to make it up in the afternoon. Today's two updates, please forgive me!

In addition, I would like to recommend a book, which is linked below.