sentences:  On 26 March, the enemy broke through the lines, and Allied forces began a withdrawal with the force under Harman conducting rearguard actions.By this time, the German advance had penetrated up to into Allied positions; however, by this time supply lines were beginning to be stretched, and Ludendorff diverted his objectives and thus lost some momentum of his attack while he attempted to drive a wedge through between British and French forces.By 30 March the attack was renewed; however, by this time the Allied forces had rallied and received reinforcements.