The interracial roommates spent less time together, and had fewer joint activities than the white pairs.
出自-2012年6月听力原文
They generally spend more time together that white pairs
出自-2012年6月听力原文
1 million breeding pairs - will be forced to relocate their breeding grounds, or face extinction by 2100.
2019年12月六级真题（第三套）阅读 Section C
They cited a study presented earlier this year of 249 pairs of parents and their children in which twice as many children as parents wanted rules on what parents could share.
2018年12月六级真题（第三套）阅读 Section B
柯林斯高阶英汉双解学习词典释义
N-COUNT
双；对；副
A pair of things are two things of the same size and shape that are used together or are both part of something, for example shoes, earrings, or parts of the body.