form、figure、shape和outline这些名词均有“形式”或“外形”之意。
form : 最普通用词，含义广，既可指客观物体的外形，又可用于抽象概念的“形”。
- I could just about make out his sleeping form on the bed.
我只能隐约看出他在床上睡觉时的轮廓。 - The moon highlighted the shadowy forms of the hills.
月光凸显了山峦影影绰绰的轮廓。 - The lawn was laid out in the form of the figure eight.
草坪被设计成了8字形。
figure : 指轮廓、外形，尤指体态，相貌或身体。
- I could see two tall figures in the distance.
我可以看见远处两个高高的人影。 - A strange bearded figure (= person) entered the room.
一个留着络腮胡的陌生人走进了房间。
shape : 通常指由线和面所围成的外观上的形，侧重立体形状。
- Clay can be moulded into almost any shape.
黏土可以塑成几乎任何形状。 - These bricks are all different shapes.
这些砖形状都不同。 - Kim's birthday cake was in the shape of a train.
金姆的生日蛋糕是火车形状的。 - Our table is oval in shape.
我们的饭桌是椭圆形的。
outline : 指任何形状的轮廓线。
- She drew the outline of the boat and then coloured it in.
她画了这只船的草图，然后给它着色。
