Complex sentence: At the age of 23, already an experienced flight instructor at the Frunze flight club in Moscow, in 1938 she graduated from the Moscow Aeroclub and in 1940 she began training in military aviation.
Split into simpler sentences: At the age of 23, already an experienced flight instructor at the Frunze flight club in Moscow. In 1938 she graduated from the Moscow Aeroclub and in 1940 she began training in military aviation.