1. She added a postscript to her letter.
    她在信末又附了一笔。

1.

1. 附言：此外有些信件还有事由(Subject Heading),附言(Postscript),附件(Enclosure)等一些特殊而不常用的项目. 各部分都有一定的格式和位置,除私人信函外,正式或公务信函通常都是用打字机打出的. 例:

1. （信末署名后的）附笔，附言，又及
    A postscript is something written at the end of a letter after you have signed your name. You usually write ''PS'' in front of it.

    e.g. A brief, handwritten postscript lay beneath his signature.
           在他的签名下，有一句简短的手写附言。

2. （加在故事、记述、声明末尾的）附言，补充说明；补编；跋
    A postscript is an addition to a finished story, account, or statement, which gives further information.

    e.g. As the editor''s postscript reminds the reader, she was to endure two more spells of mental illness before the book was published...
           正如编辑在附言中提醒读者的那样，她在本书出版前还要再经历两次精神疾病发作的折磨。
    e.g. I should like to add a postscript to your obituary for John Cage.
           我想在你为约翰·凯奇写的讣告后补充一点内容。

1. textual matter that is added onto a publication
    usually at the end

    Synonym: addendumsupplement

2. a note appended to a letter after the signature

    Synonym: PS