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| A. His father began to do business after the reform and opening-up(改革开放). And his family got a motorbike, a TV set and a fridge. B. His family spent much time travelling every year. But he was busy on weekends because his mother sent him to a lot of classes. C. He liked doing sports a lot and his favorite sport was ping-pong because lots of people at that time liked this activity very much. D. He was in poor health because he didn’t do much exercise. Worse still, he liked eating junk food very much. So the doctor advised him to go on a diet. E. Surfing the Internet was very popular when he was young. He got a mobile phone when he went to school. And he often watched movies at the cinema. F. Jumping rope and playing hide-and-seek were his main activities in his childhood. He went to bed early at night because there was no TV. G. At first, he played computer games in the net bars. Then his family got a computer and he could do it at home. Of course, he did lots of useful things on computers. |
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
