2, there is no difference, just use it casually, and the sentence will do.
3, nothing special, you can open it or not.
4. You can find the full text of the manual by searching on the official website of China National Intellectual Property Administration. I want to say a few points, and it is best to find the description of the invention patent; Want to know the writing format of patent documents, find domestic patents, concise and clear; Want to know more about writing skills and find foreign patents.
If you want to know, patent agents will lose their jobs. Self-study is difficult. Employees of patent agencies spent seven or eight years taking the patent agent qualification examination, but they failed, not to mention you just sat in front of the computer and searched.