periodical working

例句：

1. 1. The magazine has a monthly circulation of 500,000 readers.
   这本杂志每月有50万读者。
2. 2.The research paper is based on the findings of a periodical survey.
   这篇研究报告是基于一项定期调查的结果。
3. 3.The book is a collection of periodical articles about history.
   这本书是关于历史的定期文章集。