Fig1.Emails prevail now, but do use envelopes in formal occasions instead.

　　Fig2.Open-window envelopes, showing receivers' names&addresses, may inaugurate repeated printout.

　　Fig3.A big chopper is needed to open Weiwu's snail mails for they are sealed with strong parcel tape.

　　Fig4.Self-seal means adhesive tapes attached, so not the mails but you should accomplish the sealing job instead of open-wide delivery.

　　Fig5. Xiaoli always blushed the receptionist while asking for more“gussets”envelopes stocked. Just call them“triangle seals”, ok?

　　Fig6. A tip: As a general rule. Brown for public purposes and white for private or biz ones.

　　图一：这是一个电子邮件横行的年代，但正式的商务场合还是请用信封。

　　图二：使用开窗式信封来显示收信人的地址和姓名是重复打印的悲剧的开始。

　　图三：魏武经常用最结实的封箱胶带封信封口，我想收信者没有一把好刀是肯定看不到信的内容的。

　　图四：自封信封意思是信封口上面带着双面胶，不是信封自己会把自己封上，不要敞着就寄出去了。

　　图五：小李总是要前台多备一些“三角护翼”的信封，听的那个小丫头总是面红耳赤的，还是说“三角形封口”好点。

　　图六：小常识：一般公认棕色信封是给发广告信用的，而白色信封是私人或商务使用。