unfrequent造句

• Ten years ago , the paging set pager is very unfrequent . now it is not rarity
  十年前，寻呼机挺少见的，现在太不稀罕了。
• " george , i let mary go yesterday , " was not an unfrequent salutation at the dinner table
  “乔治，我昨天把玛丽打发了。 ”这一类谈话在他们家饭桌上经常可以听到。
• During ion source operating , alternating axial magnetic field and azimuthal electric field in discharge tube ionize hydrogen gas purified by hot palladium pipe , and form plasma , hi fifties year , research reports studied on rf ion source are numerous however most of them are concerned about application , and research reports relevant to discharge theory or experiment model are unfrequent
  离子源工作时，放电空间交变的轴向磁场和涡漩电场激发放电管中经钯管纯化后通入的氢气电离，形成等离子体。 50多年来，关于高频离子源的研究报告很多，但是，这些研究主要都集中在应用研究方面，有关高频无极环形放电离子源的理论与实验模型研究不是很多。