Completeness
A business communication should include all the necessary information. It is essential to check the message carefully before it is sent out.
信的内容完整，结构完整。

Correctness
Correctness means appropriate and grammatically correct language, factual information and accurate reliable figures (such as names of articles, specifications, quantity, price and units, etc.)
至关重要的一点。一封信中传达的信息如果不正确，那么，前面所说的六点做得再好也只是前功尽弃。正确除了内容正确外，语法也要正确，使用的商业术语、信的组织结构、标点符号、字母的大小写也要正确，还要保证数字、日期、地点、商品名称等等的正确。