periodic

periodic periodic sentence periodic sentence是什么意思 什么是Periodic sentence? what is periodic sentence?(the definition of periodic senten 论述题 What is a periodic sentence? on a periodic basis什么意思 英语翻译periodic reporting for planned heritage preservationback According to the periodic table ,( )still some elements undi Wynn Company use the periodic inventory system to account fo 英语翻译Periodic structures generally exhibit passband and stopb 英语翻译语境：Regularly schedule housekeeping tours and periodic se