线材拉伸时受到三个外力即线端的拉伸力、模孔变形区的正压力、线材后端的反拉力。
参考答案：错
下列各组物质的名称或俗称与化学式不相符的是[ ]
A．CaCO3 石灰石 碳酸钙
B．CaO 生石灰 消石灰
C．Ca（OH）2 熟石灰 氢氧化钙
D．NaOH 烧碱 苛性钠
. There is a tradition of having a family dinner at home on lunar New Year’s Eve.
_____, however, the custom has changed.
A．Late
B．Later
C．Lately
D．Latter
