sentences:  He then accepted an Estonian citizenship but remained in Beijing.With the recommendation of his friend Charles Eliot, the then principal of the University of Hong Kong, he was invited by Hu Shih to teach Sanskrit, Tibetan and History of Indian Religion in the Peking University, as lecturer from 1918 to 1921 and as professor from 1922 to 1929.He helped set up the Sino-Indian Institute in Beijing in 1927.