用作定语
▲～+n.
It's a horizontal line.这是一条平行线。
The lake has a horizontal surface.湖面呈水平状。
用作表语
▲S+be+～
Stand the table on its legs, so that the top is horizontal.把这桌子立起来,使桌面成水平状。

horizontal还可用作名词,意为“水平位置”。例如:
He shifted his position from the horizontal.他从水平姿势变换成其他姿势。