当状语从句的主语与主句的主语是同一个人或物时,且从句中含有be动词时,就可省略主语及be动词.
when invited by the hostess是过去分词结构作状语,就是省略的时间状语从句
因此,when invited by the hostess=when they are invited by the hostess
they 指代people .
所以,when后面没有be动词.
当状语从句的主语与主句的主语是同一个人或物时,且从句中含有be动词时,就可省略主语及be动词.
when invited by the hostess是过去分词结构作状语,就是省略的时间状语从句
因此,when invited by the hostess=when they are invited by the hostess
they 指代people .
所以,when后面没有be动词.