1, the video has no depth and rigidity, and the project video is almost worthless. 2, the service is very poor, QQ service is nominal, and teachers can't be criticized, and criticism is directly blacked out; 3. After buying the video, it is almost a one-time business. If you want a computer and an account password, you won't delay for various reasons. When Taobao complained that China was embedded, they used the false perjury information of customers who traded on different dates or their vests to deceive Taobao customer service to successfully solve the problem; 4. If you criticize them on QQ or Want Want again, you will do something to get back at users after the video disappears for a while.