Complex sentence: Lieutenant Colonel Georges Thenault with his family (wife Sarah, children Catherine and George) were residing in France when World War II erupted, at 56 Rue Tahère Saint-Cloud-western suburb of Paris.
Split into simpler sentences: Lieutenant Colonel Georges Thenault with his family (wife Sarah, children Catherine and George) were residing in France when World War II erupted. Their residence was 56 Rue Tahère Saint-Cloud-western suburb of Paris.