America challenges China at WTO over China's export subsidies. ANBOUND research team suggests that this means America’s focus on trade sanctions against China has gone deeper, which should attract great attention from Chinese government, and which means US has already paid close attention to substantial mechanisms and arrangements such as demonstration bases, development zone, demonstration zone, etc. This indicates that American has made deep investigation into China. Now that American government has challenged China, sanction policies might be introduced very soon. China should pay close attention to relevant actions and make response plans in advance.