They are also attempting to keep the car buyer as a long-term customer by offering after-sales service.他们也在试图用提供售后服务的办法留住购车者，使他们成为长期客户。Its chief selling point is the undoubted superiority of its after-sales service.它的主要卖点是其毋容置疑的优质售后服务。We offer excellent after-sales service on all our goods.我们对所有的商品提供高品质的售后服务。