The cardiovascular system is the heart and all of the passages that carry blood throughout the body.
The cardiovascular system is the heart and all of the passages that carry blood throughout the body.
新的发现使部分专家提出现今的污染控制力度也许还不够。
The cardiovascular system is the heart and all of the passages that carry blood throughout the body.
新的发现使部分专家提出现今的污染控制力度也许还不够。