Deflection with a "Dead Spear"
The above 2 Spear stances are from the Chinese Long Spear manual, which depict the Spearman performing deflections single-handedly. These are used when you have a "dead Spear". Say you've just performed a single-handed thrust with a Spear, and the enemy hammers it down to the ground. You are now in a vulnerable situation with a "dead Spear" that you can't thrust with.
The enemy is sure to launch his own counter-attack right after. The quickest way to save yourself is to deflect away his attack, by using one of the 2 stances as shown. One for deflecting to the left, and one for the right. You may also observe similar deflection techniques when using a single-handed sword, with the overhand and underhand blocks.
Jack Chen Ancient Chinese Martial Arts Manuals