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Mr. Black is a policeman. He always gets up early. He is never late for work. He goes to work by bike. He thinks it is a good exercise. He likes to help others. He often helps old people on the road. Yesterday was Christmas. There were many people outside. He saw an old woman with a big bag. He helped her to carry the bag. The old woman said, “Thank you, sir. And Merry Christmas!”
1．Mr. Black is sometimes late for work.2．Mr. Black takes a walk to work every day.
3．Mr. Black often helps old people on the road.
4．Yesterday was January 1st.
5．Mr. Black helped the old woman to carry a big bag.
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
