Here are three comparative idioms that are commonly used in English: 1. As busy as a bee: Meaning very busy or industrious. Example: "During the holiday season, the shops are as busy as bees with shoppers." 2. As light as a feather: Meaning very light in weight. Example: "The package was as light as a feather, making it easy to carry." 3. As clear as day: Meaning very clear and obvious. Example: "Her explanation was as clear as day; everyone understood it easily."