1.
An envelope or wrapper for mail.
封套，信封为邮寄而制的信封或封套
2.
The information is sent in a sealed envelope.
信息用封口的信封寄出。
3.
He licked the gummed flap and sealed it shut.
他舐了舐信封的胶水层，封上了信封。
4.
a self - sealing envelope.
（不用胶水）封口的信封
5.
We seal the back of envelopes.
我们把信封的背面封上。
6.
He sealed the envelope with paste.
他用浆糊封好信封。
7.
an adhesive envelope
封口涂有胶水的信封
8.
The envelope' s seal was torn open.
信封封缄被撕开了。
9.
The ( flap of the ) envelope was unstuck.
信封（的封口）没粘住.
10.
Can you make head or tail of the letter?
你看得懂这封信封吗？
11.
stick down(the flap of)an envelope
粘住信封（的口盖）.
12.
tuck the flap of an envelope in
把信封的口盖摺进信封里.
13.
The information is send in a sealed envelope.
信息是放在一个封口信封里发走的。
14.
Special postal envelope Envelopes of domestic express mail
GB/T17128.1-1997邮政特种信封邮政快件信封
15.
You must seal up the envelope before mailing the letter.
你在寄信前必须先将信封密封。
16.
Fold the letter before putting it in the envelope.
把信摺起来再装入信封.
17.
Double your letter up before putting in into the envelop
装信封前先把信折叠好。
18.
Fold the letter and put it in an envelope.
将信折好放进信封。