after是一个相当特殊的词 既是连词 也是介词 (before也是同理)
例如：After he was interviewed,he succeeded in being employed.这句是对的.
但是,当把after状语从句的主语he省略掉的时候,after会被自动认为是一个介词,所以after being interviewed,不是表示“在正在被面试”,而是因为after是介词,后接动词ing形式而已.After being interviewed和before being accepted均为正确的表达,是介词后接动词短语的语法点考查.
其他的连词,像when,if,因为它们没有其他词性,所以不会产生像after一样的问题.
例如：When he was interviewed,he appeared calm and confident.可改动成：When interviewed,he appeared calm and confident.
恩 必须是before being fully accepted.before此处只能看成一个介词咯,如果不能明白直接短信我
呃 我看到你逐渐钻到牛角尖里头了
before / after有两个词性,后接从句(有主语)的时候,看成连词,这点相信你能理解.
但问题来了,当它接的是名词或动词(无主语)的时候,它就是个介词了,别把它看成省略主语的省略句,因为after / before本身具备两个词性,所以它无法像when,if一样进行你所熟知的省略