Complex sentence: He studied teacher training and in 1934 began his career, but after the spanish civil war he was sanctioned for his afiliation to Alianza Republicana and for his work as Secretary of the Unión General de Trabajadores.
Split into simpler sentences: He studied teacher training and in 1934 began his career. After the spanish civil war he was detained for his afiliation to Alianza Republicana and for his work as Secretary of the Unión General de Trabajadores.