2. Purchase method: explain the channels for students to purchase courses, such as official website purchase, WeChat purchase and telephone purchase.

3. Payment methods: list acceptable payment methods, such as Alipay, WeChat payment, bank transfer, etc.

4. Refund policy: List the conditions and regulations of refund in detail, such as the refund period, whether to charge the handling fee and the refund method.

5. Precautions: List the terms and matters that students need to pay attention to when purchasing courses, such as the deadline for registration, the validity period of courses, and the arrangement of course contents.