sentences:  On 21 May the PAVN hit the Marine defenses in an attempt to regain the initiative.After achieving an initial breakthrough the PAVN were forced back by the 3rd and 6th Battalions which regained their original positions by the evening of 22 May.On 24 May with support from the 9th MAB the 147th Brigade conducted an amphibious assault at Wunder Beach 10km north of the My Chanh Line and a heliborne assault 6km inland at Co Luy.