The venae cavae empties the deoxygenated blood into the right atrium of the heart.

腔静脉将脱氧血注入心脏的右心房。

So this trip from the left ventricle of the heart, to the body, and back to the right atrium of the heart is called the systemic circulation.

血液从左心室到身体，再回到心脏的右心房的行程，被称为体循环。

The venae cavae has two divisions: the superior vena cava and the inferior vena cava, and these divisions both return blood to the right atrium of the heart.

上腔静脉和下腔静脉，这些分支都将血液回流到心脏的右心房。

In other words, it drains deoxygenated blood from the legs, back, abdomen and pelvis, and then it transports them all the way up to the right atrium of the heart.

换句话说，它从腿部、背部、腹部和骨盆排出脱氧血，然后将它们一直输送到心脏的右心房。