Complex sentence: With the Second World War at its destructive zenith, many of Sloan's contemporaries enlisted in the British armed services to fight abroad, however his work manufacturing munitions at the Shanks factory in Barrhead was considered a "reserved occupation" and he remained in Scotland.
Split into simpler sentences: With the Second World War at its destructive zenith, many of Sloan's contemporaries enlisted in the British armed services to fight abroad. However, his work manufacturing munitions at the Shanks factory in Barrhead was considered a "reserved occupation" and he remained in Scotland.