1）After considering the choice in detail：介词短语,做时间状语,其中After是介词,而considering the choice in detail是动名词短语,做After的宾语,叫介词宾语,动名词后又接the choice 这个宾语,而in detail则又是一个介词短语,做considering 的状语.译文：在详细考虑了所做的选择之后
2）it was agreed that Miss Susan Wenworth be co-opted as Social Convener：这是一个含形式主语的复合句,形式主语是it,而真实主语是that Miss Susan Wenworth be co-opted as Social Convener.第一部分,即it was agreed ,是被动语态.第二部分由 that一词引出,Miss Susan Wenworth be co-opted as Social Convener中的主语是Miss Susan Wenworth ；谓语部分是 be co-opted ,要注意的是这是虚拟语气形式.句尾的as Social Convener可以看做该小句中Miss Susan Wenworth的补足语,即主语补语.