Von Frisch knew from experiments by an earlier researcher that if he put out a bowl of sweet sugar syrup, bees might at first take some time to find it but, once they had done so, within the hour, hundreds of other bees would be eagerly taking the syrup.(剑4, General Training Test B section3)
● 分析：
本句的主句为“Von Frisch knew from experiments by an earlier researcher that…”; “that if he put out a bowl of sweet sugar syrup, bees might at first take some time to find it but, once they had done so, within the hour, hundreds of other bees would be eagerly taking the syrup”为that引导的宾语从句，做knew的宾语;句子“if he put out a bowl of sweet sugar syrup, bees might at first take some time to find it”和句子“once they had done so, within the hour, hundreds of other bees would be eagerly taking the syrup”并列，由but连接;句子“if he put out a bowl of sweet sugar syrup, bees might at first take some time to find it”中的“if he put out a bowl of sweet sugar syrup”为if引导的条件状语从句;句子“once they had done so, within the hour, hundreds of other bees would be eagerly taking the syrup”中的“once they had done so”为once引导的时间状语从句。
● 题目：
In the first type, a returning scout scampered in circle, alternating to right and left, stopping occasionally to regurgitate food samples to the excited bees chasing after her.(剑4, General Training Test B section3)
● 分析：
本句主句为“a returning scout scampered in circle”; “alternating to right and left”和“stopping occasionally to regurgitate food samples to the excited bees chasing after her”均为现在分词短语做伴随状语，引导词省略;“chasing after her”为现在分词短语做定语，做bees的定语。
