This problem is in Contest(s) below:
Contest 22:24秋冬信奥语法初级1班作业(二)
Contest 186:2025秋冬信奥语法初级班第三次作业
Contest 158:第六期信奥启蒙营 Day3
Contest 209:25秋冬语法初级周六1400第四次课