中文：

毛利率是企业在一定期间内所获得的毛利润与销售收入的比率。它反映了企业盈利能力的强弱和市场竞争力的大小。毛利润是指销售收入减去直接成本后的利润，而毛利率则是毛利润与销售收入的比率。

毛利率计算公式为：毛利率 = (毛利润 / 销售收入) × 100%。例如，如果某企业在一定期间内销售收入为100万元，毛利润为30万元，则该企业的毛利率为(30 / 100) × 100% = 30%。

毛利率的大小对于企业来说具有重要意义。高毛利率意味着企业具有较高的盈利能力，能够更好地实现价值创造和效益提升。同时，高毛利率也意味着企业在市场上具有更强的竞争力，能够更好地抵御竞争对手的挑战。因此，企业需要通过对毛利率的计算和分析，及时发现和解决经营中存在的问题，提高企业的盈利能力和市场竞争力。

英文：

Gross profit margin is the ratio of gross profit to sales revenue within a certain period of time, reflecting the strength of the enterprise's profitability and market competitiveness. Gross profit refers to the profit after deducting direct costs from sales revenue, and gross profit margin is the ratio of gross profit to sales revenue.

The calculation formula for gross profit margin is: gross profit margin = (gross profit / sales revenue) × 100%. For example, if a company's sales revenue is 1 million yuan and its gross profit is 300,000 yuan, then the company's gross profit margin is (300,000 / 1 million) × 100% = 30%.

The size of the gross profit margin is of great significance to enterprises. A high gross profit margin means that the enterprise has a high profitability, better ability to create value and improve efficiency. At the same time, a high gross profit margin also means that the enterprise has stronger market competitiveness and can better withstand challenges from competitors. Therefore, enterprises need to calculate and analyze the gross profit margin in order to timely detect and solve problems in their operations, improve their profitability and market competitiveness.