【正文】
recreation and education for human beings. What kinds of function of estuaries have been mentioned in the passage? (1)Why are estuaries such good places for nature’s young one? (2)What does density mean in this passage? (3)How do estuaries affect the water that passes through them? (4)Why are estuaries more sensitive to pollution than other areas? (5)Why are estuaries important to human beings? 1. Why are estuaries such good places for nature’s young ones? In estuaries, animals can enjoy all the benefits of the oceans without having to face many of its dangers. Tides provide energy for the ecosystems, but estuaries are protected from waves and storms by islands, mud or sand. Nutrients from both the land and the ocean arrive in estuaries. Read the passage and answer the following questions. 4. Why are estuaries more sensitive to pollution than other areas? Because estuaries act as filters(過(guò)濾器 ), many pollutants end up in them. 2. What does density mean in this passage? It means the number of species per area. 3. How do you estuaries affect the water that passes through them? They absorb nutr