Translation (翻译)1. 兼职工作为我们提供了锻炼的机会。（provide… with）2. 促销对于一种产品来说是有必要的。(promotion)3. They do the research on market potential to see if they will make money by selling the products in the new market.4. Any maintenance or serving the company does after it has sold the product is called after-sales service.5. Whether a company can provide good after-sales service or not may directly influence the sale of its products.