venous blood

例句：

1. 1.Blood flows through the venous system to the heart.
   血液通过静脉系统流向心脏。
2. 2.The doctor examined her venous pressure.
   医生检查了她的静脉压。
3. 3. The patient's venous return was slow.
   病人的静脉回流缓慢。