2017考研英语长难句分析每日一句(831) Demand comes mainly from two sources: independent mom-and-pop grocery stores,which, unlike large retail chains are too small to buy straight from producers and food service operators that cater to consumers when they don't eat at home.
【分析】多重复合句。句子主干为 Demand comes mainly from two sources。冒号后的部分列举 twosources:一是 independent mom-and-pop grocery stores,二是 food service operators,两者分别由 which 和 that 引导的定语从句修饰。which 从句中使用了too...to“太...以至于不能”句型,作比较状语,that 从句中又包含一个 when 引导的时间状语从句。