四个数字有多少种组合两位数简介:In the second-grade teaching building, Lao Song, the dean of teachers, patrols the corridors from time to time, mainly visiting the boys' toilets on each floor. Su Can was very lucky. When he met Lao Song, who had a day off today, he quickly jumped to the back door of his classroom.
In the second-grade teaching building, Lao Song, the dean of teachers, patrols the corridors from time to time, mainly visiting the boys' toilets on each floor. Su Can was very lucky. When he met Lao Song, who had a day off today, he quickly jumped to the back door of his classroom.