邀请信属于重要社交类信件，一般篇幅较短，措辞有礼，用以联络亲朋、增进感情。邀请信有很多种类， 适用于各种场合，如婚庆、酒宴、聚会等。按文体可分为正式和非正式两种。一般来讲，邀请信的正式程度要视具体场合而定。当然主人的兴趣品味也是决定信件文体风格的重要因素。此外， 与邀请信内容有关的还有接受邀请信和拒绝邀请信，写法上也各有其特点。 The invitation letter is an important social letter. It is generally shorter in length and more politely used to connect relatives and friends and enhance feelings. There are many types of invitation letters, suitable for various occasions, such as weddings, banquets, parties and so on. According to style, it can be divided into formal and informal. In general, the formal degree of an invitation letter depends on the specific situation. Of course, the owner’s interest in taste is also an important factor in determining the style of the letter. In addition, there are invitation letters and rejection letters related to the content of the invitation letter. Their writing methods also have their own characteristics.