集

• it constitutes a presheaf of ring on the basis of open sets. (xf)fa .
  这构成了开集基（Xf）fA上的环的予层。
• Today a 1967 cougar in good condition is a collector's item .
  到今天，一辆没有破损的1967年生产的美洲豹车是汽车搜集家的一项瑰集品。
• The conviction came as a shock, and she stood still in a flurry of thought .
  这一肯定之后，她就象触电一样，站在那里不动，思绪纷集。
• Around the morgan and rockefeller empires clustered a number of smaller kingdoms .
  在摩根和洛克菲勒帝国周围，麇集着一些较小的王国。
• A device widely used with gto basis functions is that of a contracted gaussian set .
  广泛地应用GTO基函数的一个方法是简缩高斯函数集。
• An increasing path from (0, 0) to (n, m) is a set of lattice edges .
  每一条由（0，0）到（n，m）的递增通道是平行于坐标轴的线的一个集。
• It is necessary to enrich the fuel by increasing the percentage concentration of uranium-235 .
  必须提高铀235浓度的百分比，使燃料浓集。