The United Nations says nearly 60 percent of Afghanistan is insecure to a greater or lesser extent, and access in these areas is limited and risky.

VOA: standard.2009.08.07

It at least overlaps to a greater extent than most of the other books.

它起码与很多其他的课本,重复了很多部分。

麻省理工公开课 - 固态化学导论课程节选