[解析]
Dear Tom,
It is so considerate of you to receive your letter inquiring about novel cononavirus pneumonia in China and showing worry about me. 【高分句型一】I am writing to share with you what I'm doing in the epidemic situation.(感谢他的关心并且点明书信主题)
Since the outbreak of an infectious disease in wuhan in December 2019,the Chinese government has decisively closed down the city to prevent the spread of the disease.【高分句型二】At this particular time,I go out as little as possible.If I go out,I must wear protective masks to prevent myself from getting infected.In addition,I keep good healthy habits and keep my body clean.(应对措施)
Thank you for your concern.I'm definitely convinced and looking forward to that we can get through the hard times.(自己的盼望)
Yours,
Li Hua