Can. The implementation of the national six policy, and will not affect the existing national five cars on the road normally, as long as the national five cars according to the requirements of the regular inspection, to meet the requirements of the national emission regulations, you can always use. As long as we are in accordance with the requirements of the periodic inspection, there is no problem is allowed on the road. General modification if to meet the requirements of the Ministry of Industry and Information Technology, then are legal, can be normal on the road. But it is not recommended to modify, because we do not know the situation after modification. Unauthorized modification of vehicles is illegal, seriously endangering their own lives and the lives of others. I hope you strictly abide by road traffic laws and regulations to create a safe, smooth, civilized and harmonious road environment.