She called on Eritrea to clarify the whereabouts of 11 MPs who disappeared without a trace in September,2001.

VOA: standard.2009.04.09

We are also put in mind of how the war is, in fact, anything but a revel, though it, too, may have been provoked by a cause as insignificant and hard to trace as "some wizard vermin."

我们同样也思考事实上战争，只是一场狂欢，尽管它有可能,是由一个毫不重要难以追踪的“一些害虫“引起的“

耶鲁公开课 - 现代诗歌课程节选

"When the gas comes off the digester, it has not only methane in it it also has carbon dioxide And it has a trace of hydrogen sulfide."

VOA: standard.2010.02.23