Complex sentence: This force was a shadow command structure of 6th Army and was created to avoid placing that Army under the command of Australian General George Blamey, while he was Allied Ground Force Commander in New Guinea and in nominal command of all allied ground forces.
Split into simpler sentences: This force was a shadow command structure of 6th Army and was created to avoid placing that Army under the command of Australian General George Blamey. While he was Allied Ground Force Commander in New Guinea and in nominal command of all allied ground forces.