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Lingling’s grandma was a dancer many years ago. She learnt English. She could speak English. She danced in lots of Chinese cities. But now she is old. She can’t dance. Lingling’s grandpa was a driver. He didn’t learn English. So he couldn’t speak English. But now he is learning English.
1．Lingling’s grandma was a dancer many years ago.2．Lingling’s grandpa couldn’t speak English but her grandma could.
3．Now Lingling’s grandma dances in lots of Chinese cities.
4．Lingling’s grandma is old now but she can still dance.
5．Lingling’s grandpa was a driver and he is learning English now.
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
