His mother is a nurse at a local hospital.

Tang took six online courses every day and spent the rest of the time studying on his own. He usually rose at 6:30 am and went to bed at about midnight.

"I did feel worried about my father, but I was also proud of him for risking his life to save others," he said.

The outbreak seemed to pass without Tang noticing, because he seldom left home and spent most of his time studying, he said.

His father returned home in early April as the situation in Hubei had improved greatly.

Tang's school reopened on April 7 as the outbreak eased in Huaihua. He said he is happy the gaokao has been delayed for a month because it provides extra time for preparation.

"The time I spent alone at home has made me more self-disciplined. As soon as I start studying, I seldom lose concentration and my grades are getting better," he said.

To further improve his grades, he started taking classes with Zhangmen, a provider of online tutorials for students from kindergarten through 12th grade, when he got home from school every day.

"Preparing for the gaokao is not easy-just as it is not easy for my parents trying to save patients," he said. "What I have learned from the experience is that once you put your mind to something, you will make gains."

Tang wants to become a flight attendant in the future as he has never been in a plane, he said.