It means don't disturb during the preparation. More people like to express their personal status on their personal signatures. Girls' personalized signature ashore. Do not disturb means not to disturb when preparing for the exam. Personalized signature means that after a BBS is registered, you can set the signature, that is, the text displayed at the bottom of each post, some of which look like notes. Because every netizen writes different words, such as aphorisms, proverbs, teasing sentences and so on. , but also with pictures and animations as signatures, full of personality and different styles.