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单语范例（未经PONS编辑处理）
Conservation work was undertaken in 2006 to help maintain safety and improve the understanding of the site.
en.wikipedia.org It has undertaken works in 50 countries around the world in areas of power, water resources and infrastructural development.
en.wikipedia.org Further alterations and expansions to the building were subsequently undertaken, and a research laboratory wing was added in 1994.
en.wikipedia.org To help in conservation efforts banding of the birds and frequent censuses are undertaken.
en.wikipedia.org Some students undertake their pre-university studies in private colleges.
en.wikipedia.org