咩野係tactful writing?

tactful 用中文解釋就是 <得體 / 措辭小心 / 委婉>, 好像政府的公文, 避免文句使讀者不快的, 如:
You cannot smoke on this venue. (你不可以在此吸煙)---->Thank you for not smoking on this venue. (請勿吸煙, 多謝合作)
要寫TACTFUL的文字, 可從多方面配合, 如用詞, 句式, 甚至語氣. 但你講的 positive vocabulary / impersonal contruction 確是有用的工具.
positive vocabulary 的例子:
You are not allowed to .... ----> You are reminded not to .....
Someone complained against you for...----> It has been brought to our notice that ........
用"不肯定"語氣也有幫助
You do not know ......----> You may not be aware.....
其實, 只要易地而處, 想像你是收信人, 試感受文字有沒有讓你感到被冒犯, 就可以判斷文字是否TACTFUL

Tactful writing just means writing with skills and understanding of the topic.
Normally this kind of writing will require your full analysis of the topic and elaborate it with your writing skill which shows that you fully understand the topic.
In this case you will not expect a writing for a story, a script, etc. I believe it needs your view points plus supporting arguments and conclusion.