要点如下：1. 介绍自己，写信目的。2. 说明情况，表示气愤。3. 希望重视，尽快解决。
注意：1. 词数100左右;2. 可以适当增加细节，以使行文连贯。
参考词汇：传染病，泛滥 epidemic新冠状病毒 novel coronavirus消费者协会
To whom it may concern,
I am Li Hua, a senior school student. I am extremely sorry to disturb you, but I have to write a letter to convey my complaint and dissatisfaction.The novel coronavirus epidemic is still tough and annoying. However, you can't imagine that a small number of businesses are so mean as to sell the face masks at an unreasonable price. It is said that it can be five times as high as the normal price. My classmates and I are burning with anger.I hope Consumers' Association can give much attention to this. I'd appreciate it if you can cope with it as early as you can.
Yours sincerely,Li Hua