Mary: Hello, Lucy! 1. are you doing?
Lucy: I am sending some postcards. How 2. you?
Mary: I’m sending a letter. Where are you sending your postcards?
Lucy: I’m sending them 3. America. And where are you sending your letter?
Mary: I’m sending it to Canada.
Lucy: How 4. are the stamps?
Mary: I think they are ten yuan or more.
Lucy: That’s too expensive(昂贵的).
Mary: I think so.
Lucy: Why not send an email on the 5.?
Mary: That’s a good idea. Let’s go and find a computer.

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

