不不经常的英文怎么说

"不经常" 在英语中可以用 "infrequently" 或 "rarely" 来表示。

"Infrequently" 来源于拉丁语 "infrequens"，意思是 "不常见的"。

"Rarely" 来源于拉丁语 "rarus"，意思是 "罕见的"。

例句：

I infrequently have time to watch TV. (我不经常有时间看电视。)
She rarely goes out on weekends. (她周末很少出门。)