sentences:  During World War I, his family fled to the Altai region in Siberia, where Lācis studied at the pedagogical seminary in Barnaul.In 1921, Lācis returned to Riga and at various times worked as a fisherman, port worker, ship's fireman and librarian while writing in his free time.In 1933, he published his hugely successful novel "Zvejnieka dēls" ('Fisherman's Son'), making him one of the most popular and commercially successful Latvian writers of the 1930s.