平行线

Zollner's illusion makes parallel lines seem to diverge by placing them on a zigzag-striped background.

将置于锯齿形景上，左氏错觉会让看起来不。

Parallel lines are lines that never join.

是永不相交的。

There are two parallel lines.

这有两。

Parallel lines are, by definition, lines on the same plane that never join.

按定义说, 是在同一面上永不相交的。

Graph paper, parallel, and planimeter methods are current tools for acreage calculation.

目前常用的量算面积方法有方格纸法、法、求积仪法。