同学,很高兴回答你的问题
正确答案:填have fun 或enjoy themselves
即:Children often ( have ) ( fun ) on Children's Day.或
Children often ( enjoy ) ( themselves ) on Children's Day.
翻译:孩子们经常在儿童节过得很开心.
解析:have a good time = have fun = enjoy oneself 玩得开心,过得愉快,是固定词组,其中的enjoy oneself 要根据主语变换成不能的反身代词
有不明白的请继续追问,