thin的比较级为：thinner。第三人称单数：thins；过去分词：thinned；最高级：thinnest；过去式：thinned。thin作形容词的基本意思是“薄的，细的”，引申可表示“稀的，稀疏的，稀少的”，指物体两个表面之间较“薄”或圆柱形物与高度相比较小的直径，即“细”。
thinner例句
1. She has one slightly withered leg, noticeably thinner than the other.
她有一条腿有点儿萎缩，看上去明显比另一条腿瘦。
2. The twins were dressed differently and one was thinner than the other.
这对双胞胎穿着不同，而且其中一个偏瘦一点。
3. Will you keep on the course of exercises until you are thinner?
你要继续这项训练直到身体瘦下来为止吗?
4. The clay is very stiff; we must make it thinner with water.
这粘土非常稠, 我们须用水使它变得稀一些.
5. The higher we go above the earth, the thinner the air is.
我们离开地面越高, 空气越稀薄.