Sam: Oh, it's from my pen friend.
John: Cool! Is your pen friend a boy?
Sam: No. She's a nice girl.
John: What's her name?
Sam: Her Chinese name is Li Lin, and her English name is Sunny.
John: Can she speak English?
Sam: Yes, she can speak good English.
John: Can you speak Chinese?
Sam: Only a little. But we write letters in Chinese.
John: Do you often write letters?
Sam: Sometimes. We like to send emails in English.
概述内容:
Sam has got a

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

