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Lei Feng was from Changsha. He’s very kind. He helped many people. He carried bags for the old people and gave food to children. He gave all his money to his friend’s sick(生病的) parents. Lei Feng didn’t talk about what he did. After he died in 1962, people found his diary(日记) and learned about him. Each year’s March 5th has been named as “Lei Feng Day”. On that day, students do many good things to learn from him.
1．Lei Feng was from China.2．Lei Feng gave all his money to his sick parents.
3．Lei Feng often talked about what he did.
4．Lei Feng Day is on March 5th.
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
