Complex sentence: They departed on 25 April 1942 and reached the Romanian port of Constanța on 2 May, forming "Squadriglia Sommergibili CB", under the overall command of Francesco Mimbelli.
Split into simpler sentences: They departed on 25 April 1942 and reached the Romanian port of Constanța on 2 May. They formed "Squadriglia Sommergibili CB", under the overall command of Francesco Mimbelli.