邀请信的英文：
invitation letter; letter of invitation

• The invitation says that everyone should wear a disguise.
  邀请信上说每个人都应化装。
• Invitations rained down on the visiting writer.
  来访的这位作家收到了许多邀请信.
• This new product, or rather, this new style of shirt, is not very attractive.
  这是一封信,说得更正确些,是一封邀请信.
• I got an invite from someone I knew and trusted, signed up to see what was about.
  我从一个我认识的并且信任的人那而收到了一封邀请信，就注册了，看看是关于什么的。

• Whomever you invite will be welcome.
  你邀请的任何人都将受欢迎。
• He was upset at not being invited.
  人家没邀请他，他很不痛快.
• A Bad padlock invites a picklock
  坏锁招人撬
• Entry to this competition is by invitation only.
  此次竞赛的参赛只凭邀请函。
• She was favored with an invitation.
  她受到了邀请。

• in letter and in spirit
  在字面意义和精神实质上|无论形式和实际
• The letter was a forgery.
  这封信是伪造的。
• Post the letter through the slit in the letter box.
  把这封信从信箱的投信口投进去。
• Imprint a postmark on a letter =imprint a letter with a postmark
  盖邮戳于信上
• The letter is directed to him.
  这封信是写给他的。