1. We must ________. (保持教室清洁)
2. Look, they are ________. (等待他们的英语老师)
3. In class, we mustn't talk. We must ________. (听老师讲课)
4. In the park, we should obey the ________. (公园规则)
5. We must ________ (保持安静) in the library.
6. We must not ________. (在草地上行走)
7. We must not ________ (丢垃圾) in the playground.
8. Please ________ (摘花) for me.
9. We can see many ________ (孩子们) in the playground.
10. —Shall we go there ________ (乘车)?—Yes, go ahead.
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