British and French forces are attacking to the north of Ypres. Despite the recent unrest in their army, the French have made the best progress but neither of the Allies are doing very well. Unseasonal rain has turned the ground into a quagmire, making it difficult for the troops to move forward.
Because of the waterlogged nature of the ground, the Germans have built pillboxes for themselves rather than relying solely on trenches. The British had hoped to attack these with tanks, but the mud has made it impossible for them to get beyond their own lines.
The Allies make some gains, though they lose some of these to German counter-attacks. In view of the terrible weather conditions they now call a temporary halt to the offensive, hoping that a break in the rain will allow the ground to dry out somewhat, at which point the attacks can resume.
Mud (WW1 World War One Ieper 1917)
Escorting German prisoners (Wikipedia: Battle of Langemarck (1917))