Simplify the following text for a Grade 9 native English-speaking person.
Original: `` In the 1930s , Shi was a strong supporter of the Human Rights Defense Alliance established by Madam Soong Qing Ling , the second wife of revolutionary leader Dr Sun Yat-sen , with Cai Yuanpei and Lu Xun . ''
Simplified: `` In the 1930s , Shi was a strong supporter of the Human Rights Defense Alliance established by Madam Soong Qing Ling . Soong Qing Ling was the second wife of revolutionary leader Dr Sun Yat-sen , with Cai Yuanpei and Lu Xun . ''