— Mr. Brown, this is Mr. Smith.
— Very pleased to meet you, Mr. Smith.
A:surprised
B:glad
C:lucky
我是拼音小能手。
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灯芯
耻辱
熄灯
汹涌
已知M(x0,y0)是双曲线C: x22−y2 =1上的一点,F1,F2是C的两个焦点,若 MF1→⋅MF2→ <0,则y0的取值范围是( )