I saw someone reply that a period is easily confused with a percent sign or a corner sign 0. I think this is sheer nonsense. As long as we follow the rules of punctuation in Chinese grammar, it is impossible to cause confusion by using a period at the end of Chinese characters and a period at the end of letters, numbers or symbols. Moreover, there are obvious differences between a period and a percent sign, a corner sign 0 or the letter O on printed matter, which can be distinguished at a glance.