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In Australia, National Tree Day is on the last Sunday in July. In China, Tree Planting Day is on March 12th. Trees are very useful in our life. We can get a lot of things from trees. We get fruits from trees. We also get wood from trees. We use wood to make pencils, desks and chairs. We can use wood to make paper(纸), too. Trees are homes for birds and some other animals. Trees can keep the air clean. They can cool the air, too. Trees become green in spring and colorful in autumn. They make our city beautiful. So we should love trees. Spring is the best season to plant trees. We should plant more tress.
1．In China, Tree Planting Day is in July.2．We can get many things from trees.
3．We can’t use wood to make desks or paper.
4．Sometimes trees make the air dirty, but they can cool the air.
5．We should plant more trees.
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
