纵波是指介质中质点振动方向与（）的波。
参考答案：波的传播方向一致
下列表达式中，表达式______的运算结果与其他3个不同。
A．Int(-3.5)-1.5
B．Int(-4.5)+0.5
C．-Abs(-4.5)
D．Fix(-4.5)-0.5
—The ______ girl has learned a lot about China from her father and her school.
—She likes ______ culture very much. [ ]
A. 15-year-old; China
B. 15-year-old; Chinese
C. 15 years old; Chinese
D. 15 years old; China
