在同一平面内的两条直线叫做平行线.______.(判断对错)
因为在同一平面内不相交的两条直线叫做平行线;
所以上面的说法是错误的.
故答案为:×.
China supplies more than 90 percent of the world’s rare earth metals, but its reserves only ________ about one-third of the world’s total.
A.take up
B.make up
C.build up
D.set up
菜粉蝶对()有一定趋性。
A.稻酮
B.泡桐叶
C.芥子油
D.绿色