呼吸系统是身体里帮我们呼吸的部分，比如鼻子和肺。

The 呼吸系统 is the part of the body that helps us breathe, such as the nose and lungs.

我们常在生物课或看病的时候听到这个词。

We often hear the word 呼吸系统 in biology class or at the doctor's office.