书信是一种应用文。写信之前。要先把书信的格式弄清楚。书信包括称呼、正文、结尾、署名、日期五个部分。称呼要顶格写在第一行，后面加冒号，表示下面自己要说话。给长辈写信，必须写称谓，如爸爸、奶奶等，直呼其名是不礼貌的。称呼前还可以加上一些表示敬意的词。信的正文 Correspondence is a kind of application. Before writing. The format of the letter must first be clarified. Letters include title, body, end, signature, date five parts. The top of the call to write in the first line, followed by a colon, said below to speak. To write letters to elders, you must write the title, such as father, grandmother, etc., address him by name is impolite. You can also add some words of respect before you call. The text of the letter