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Plants are very important living things. Life could not go on if there were no plants. This is because plants can make food from air, sunlight and water. Man and animals cannot make food from air, sunlight and water. Animals get their food by eating plants and other animals. Therefore animals and man need plants in order to live.
There are two kinds of plants: flowering plants and non-flowering plants. Flowering plants can make seeds. The seeds are protected by the fruits. Some fruits have one seed, some have two, three or four, and some have many seeds. But a few fruits have no seeds at all. An example of (例子) a fruit without seeds is the banana fruit. Most non-flowering plants do not grow from seeds. They grow from spores (胚芽).
1. Why the plants are so important to animals?
2. How many kinds of plants can we find around us?
3. Can you give an example (例子) of non-flowering plants?
同类型试题
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
