Complex sentence: Admiral of the Fleet Sir John Michael de Robeck, 1st Baronet GCB, GCMG, GCVO (10 June 1862--20 January 1928) was Royal Navy officer who commanded the Allied naval force in the Dardanelles during the First World War.
Split into simpler sentences: Admiral of the Fleet Sir John Michael de Robeck, 1st Baronet GCB, GCMG, GCVO (10 June 1862--20 January 1928) was Royal Navy officer. He commanded the allied naval force in the Dardanelles during the First World War.