VOA慢速英语:老年人不是新冠病毒的唯一高危人群

mild - n. not harsh or severe

invincible - adj. impossible to defeat or overcome

transmission - n. the act or process by which something is spread or passed from one person or thing to another

role - n. a part that someone or something has in a particular activity or situation

diabetes - n. a serious disease in which the body cannot properly control the amount of sugar in your blood because it does not have enough insulin

chronic - adj. continuing or occurring again and again for a long time

immune system - n. the system that protects your body from diseases and infections

asthma - n. a physical condition that makes it difficult for someone to breathe

hormones - n. natural substances produced in the body which influence the way the body grows or develops

ovary - n. one of usually two organs in women and female animals that produce eggs and female hormones