Complex sentence: During the Second World War he served in France in 1939-40 and took part in Operation Dynamo, the Middle East where he was mentioned in despatches in 1943 and Italy in 1944-45 for which he was awarded the Distinguished Service Order.
Split into simpler sentences: During the Second World War he served in France in 1939-40 and took part in Operation Dynamo. He served in the Middle East where he was again mentioned in despatches in 1943 and Italy in 1944-45 for which he was awarded the Distinguished Service Order.