邀请信包括宴会、舞会、晚餐、聚会、婚礼等各种邀请信件，形式上大体分为两种:一种为正规的格式 (formal correspondence)，亦称请柬；一种是非正式格式 (informal correspondence), 即一般的邀请信。邀请信是在形式上不如请柬那样正规，但也是很考究。书写时应注意:
　　
    邀请信一定要将邀请的时间（年、月、日、钟点）、地点、场合写清楚，不能使接信人存在任何疑虑。例如:“I’d like you and Bob to come to Luncheon next Friday.”这句话中所指的是哪个星期五并不明确，所以应加上具体日期, “I’d like you and Bob to come to luncheon next Friday, May the fifth.”

    1. 邀请朋友共进午餐 Inviting a friend to informal luncheon

    Dear [Zhang Ying]:

    Will you come to luncheon on [Friday, May the fifth], at [twelve o’clock]?
My niece [Mary] is visiting us and I think you will enjoy meeting her. She is a charming, very pretty girl … and very good company! [John and Jane] will be here, and perhaps we can [give a dance] after luncheon. Do say you’ll come!
Affectionately yours,
Li Ming

    亲爱的[张营]:

    您能在[5月5日星期五中午12点钟] 来吃午饭吗？
我侄女[玛丽]正在我们家中作客，我想您会乐于见到她的。她是个漂亮而聪明的女孩子，……同她在一起是很使人高兴的！[约翰和简]也到这里来，也许在饭后我们能[开个舞会]，说好，一定得来呀！

    2. 邀请朋友同他们不认识的人一起共进晚餐 Inviting friends to supper with the strangers

    Dear [Susan]:

    I know you are interested in [oil painting], so I’m sure you’ll be interested in [Mr. and Mrs. Lin dun]! They are coming here to supper [next Sunday night, October the twelfth], and we’d like you and [Walter] to come, too.
[Mr. and Mrs. Lin Dun] are that very charming couple we met in [London] last summer. They have a wonderful collection of [oil paintings of various stages]; and I understand that Mr. Lin Dun is quite an authority on [oil painting]. I’m sure you and Walter will thoroughly enjoy and evening in their company.
We’re planning supper at six; that will give us a nice long evening to talk. If I don’t hear from you before then, I’ll be expecting you on the [twelfth]!
Affectionately yours,
Li Ming

    亲爱的[苏珊]:

    我知道您对[油画]是有兴趣的，所以我相信您对林顿夫妇也会感兴趣。他们将在[10月12日（下星期日）]来吃饭，我们很希望您和瓦尔特也能同来。

    [林顿夫妇]是那么好的一对夫妻。我们是去年夏天在[伦敦]认识的。他们集有[各个不同时期精美的油画作品]。我知道，林顿先生在研究[油画]方面是颇有权威的。我深信，那天晚上您和瓦尔特同他们在一起，一定会很愉快。
我们准备在6点钟吃晚饭，这样就能有较长的时间闲谈。如果事前接不到您的回信，我就指望你们那天到来。

    3. 邀请参加新厂开工典礼  Invitation to opening ceremony of new factory

    Dear [Mr. Harrison]:

    Our new factory will be commencing production on [April 10] and we should like to invite [you and your wife] to be present at a celebration to mark the occasion.
As you will appreciate this is an important milestone for this organization, and is the result of continued demand for our products, both at home and overseas. We are inviting all those individuals and trust that you will pay us the compliments of accepting.
Please confirm that you will be able to attend by advising us of your time —— we can arrange for you to be met. All arrangements for your stay [overnight on April 10] will, of course, be made by us at our expense.
Yours faithfully,

    亲爱的[哈里森先生]:

    本公司新厂将于[4月10日]开始投产，希望能邀请[贤伉俪]来参加新厂开工典礼。
如您所知，新厂的设立是本公司的一个里程碑，而这正是海内外对本公司产品不断需求的结果。我们邀请了所有对本公司的成功贡献一切力量的个人，我们相信，您一定会赏光。

    如您确能参加，请来函告知您抵达的时间 —— 以便我们为您安排会晤。当然，所有安排您在[10日晚间]夜宿的费用，皆将由公司代您支付。

    4. 邀请来家中小住及周末聚会  An invitation for a house and weekend party