Troisier's vein

例句：

1. 1. The vein in the grass is a good indicator of the health of the soil.
   草中的静脉是土壤健康的一个好指标。
2. 2. The vein in the skin runs from the heart to the lungs.
   皮肤中的静脉从心脏到肺部。
3. 3. The vein in the arm is visible when you press on it.
   手臂中的静脉在按压时可见。