a flat paper case for a letter or document, with a part that you stick down to close it before you write an address on it and send it through the post 信封
a small piece of coloured paper with a sticky substance on the back that is used for writing notes and temporarily sticking them on other papers and surfaces记事贴;报事贴
stampedaddressed envelope, or self-addressed envelope: an envelope with your name, address, and a stamp on it that you give to someone so that they can easily send you something (贴足邮票并写明姓名地址的)回邮信封
a small piece of wire that you press through pieces of paper with a small object called a stapler so that the ends of the wire bend over and fasten the pieces of paper together 订书钉
a sheet of plastic with writing or pictures on it that you shine light through in order to show the writing or pictures on a large screen (上有文字或图片的)透明正片,透明画
self-addressedstamped envelope: an envelope with your name, address, and a stamp on it that you give to someone so that they can easily send you something