Complex sentence: He held many posts within the Luftwaffe and was even delegated the leadership of the 12th Army between 2nd July 1942 and July 11th 1942, and was its Commander-in-Chief through to December 1942.
Split into simpler sentences: He held many posts within the Luftwaffe and was even delegated the leadership of the 12th Army between 2 July, 1942 and July 11,1942. He was its Commander-in-Chief through to December 1942.