组和时段

grace periods───（行动、责任等的）宽限期

ground rods───[电]接地棒

ground zeroes───“爆心投影点”组织；着地点

ground zeros───“爆心投影点”组织；着地点

accounting periods───会计期（accountingperiod的复数）

critical periods───关键期；[植]临界期

glacial periods───冰河时期

In all 24 groups, Allison's team found that animals' weight increased over periods that spanned at least ten years and often more.───通过对这24个实验组进行分析，阿里森的团队终于发现动物体重增长趋势至少要持续十年或更长间。

Both single species and whole groups of species last for very unequal periods.───单独的物种以及整个的物种群存续的时期极不相等。

In different periods of translation history, different translators put emphasis on one or more groups of those relations and put forward relevant translation criteria.───在翻译史的不同时期、不同的翻译家对这些关系各有侧重，提出了相应的翻译标准。

The analyses covered a variety of diagnostic groups, age groups, and periods.