Although boys were taught at Confucian academies for the ultimate goal of government service, girls were often taught by their brothers how to read and write. By Song times, more women of the upper and educated classes were able to read due to advances in widespread printing, leaving behind a treasury of letters, poems, and other documents penned by women. Some women were educated enough to teach their sons before they were sent to an official school. For example, the mother of the statesman and scientist Shen Kuo taught him basic education and even military strategy that she had learned from her elder brother. Hu Wenrou, a granddaughter of a famous Song official Hu Su, was regarded by Shen Kuo as a remarkable female mathematician, as Shen would occasionally relay questions to Hu Wenrou through her husband in order for her to review and investigate possible errors in his mathematical work. Li Qingzhao (1084–1151), whose father was a friend of Su Shi, wrote many poems throughout her often turbulent life (only about 100 of these survive) and became a renowned poet during her lifetime. After the death of her husband, she wrote poems profusely about poring over his paintings, calligraphy, and ancient bronze vessels, as well as poems with deep emotional longing: