用英文翻译1 血液从左心室流出到达主动脉---全身最大的动脉然后从此处血管开始进行连续不断的分支成为大大小小的血管直达全身各处。 2 整个呼吸道有三层保护屏障一是鼻毛阻挡异物如细菌、病毒和灰尘等进入呼吸道；二是气管上皮细胞分泌的粘液将异物粘住并随粘膜上皮的纤毛运动将其排出；三是肺泡内有一种细胞可吞噬肺泡内的异物。尽量高级一点

Blood flows out from the left ventricle and enters the aorta - the largest artery in the body. From there, the vessels continuously branch out into smaller and larger blood vessels, reaching every part of the body.

The entire respiratory tract is protected by three layers of barriers. Firstly, nasal hairs block foreign substances such as bacteria, viruses, and dust from entering the respiratory tract. Secondly, the mucus secreted by the tracheal epithelial cells traps the foreign substances and is then expelled by the movement of cilia on the epithelial lining. Thirdly, there are cells in the alveoli that can engulf foreign substances in the lungs