PVC塑料地板的特性有（）。
A.弹性较好
B.以聚氯乙烯树脂为主要原料
C.脚感较硬
D.常见的为单层块材
参考答案：B, C, D
开设在模具的分型面上，从塑件侧边缘进料的浇口有（）。
A、护耳式浇口
B、侧浇口
C、扇形浇口
D、潜伏式浇口
His idea of having weekly family meals together,which seemed difficult at first,has _______ many good changes in their lives.
A．got through
B．resulted from
C．turned into
D．brought about
