In this section you will find answers and instructions to the most common problems or errors. You will also learn how to report an error.
使用优惠码 EXTREME 购买 Extreme 课程（含年度会员资格）可享 7 折优惠，使用优惠码 EXTREME2 购买 Extreme 套餐可享 8 折优惠。
Errors and issues
选择一本字典
In this section you will find answers and instructions to the most common problems or errors. You will also learn how to report an error.