Zhu Wenli sang revolutionary songs so that she won't be thought of being anti-revolutionary.
Explanation:
Ha Jin's short story "A Decade" is a portrayal of the Chinese people's lives during the Cultural Revolution. China was under strict oppressive laws that tries to reassert the principles of Maoism in China.
Zhu Wenli was a young teacher in Northeast China. She used to sing Uigar folk song which was forbidden by the government under Mao Zedong. One day, one of her students heard her sing asks her what song she was singing. From the next time, she made it a point never to sing Uigar songs again. Instead she sang only revolutionary songs just so that people won't think her to be anti-revolutionary.
He advises Arthur to make a treaty with Sir Mordred for a month instead, as Sir Lancelot will come back during that month and kill Sir Mordred for him.