Complex sentence: Haking proposed to capture Aubers Ridge, Aubers and Fromelles but next day Monro dropped Aubers Ridge from the attack, as he and Plumer had concluded that with the troops available, no great objective could be achieved.
Split into simpler sentences: Haking proposed to capture Aubers Ridge, Aubers and Fromelles but next day Monro dropped Aubers Ridge from the attack. Monro and Plumer concluded that with the troops available, no great objective could be achieved.