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( )（1）A.I’m a teacher. B. He’s a doctor. C. She’s a nurse.
( )（2）A.Yes,they are. B. No,there aren’t. C. Yes,there is.
( )（3）A.It’s on the second floor.B.It’s in the sitting room. C.They’re on the first floor.
( )（4）A.He’s a policeman. B. No,he isn’t. C. Yes,he does.
( )（5）A.There are some boys in the classroom. B. There are twenty-one. C. No,there aren’t.
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
