n. 信封，封皮,壳层，外壳,包裹物,[生物学]膜，包袋
envelope可以用作名词
envelope的基本意思是“信封”,也可指“封袋”,是可数名词,有复数形式。
envelope用作名词的用法例句
There are several enclosures in the envelope.信封内装有几份附件。
I use a prepaid envelope.我用了一个邮资已付的信封。
He glued a stamp onto the envelope.他把邮票贴在信封上。
1、Return the enclosed Donation Form today in the prepaid envelope provided.
请于今日将随函附上的捐款表格用所提供的邮资预付的信封寄回。
2、Under the newspaper, atop a sheet of paper, lay an envelope.
在报纸下面的一张纸上放着一个信封。
3、The envelope has been tampered with and then taped shut again.
信封被人动过手脚，然后又用胶带封上了。