Double Knee Combo
Here is a great double knee combo from Lockflow.com model Rachel
Rachel has Landon in a clinch, pulling his head downward and keeping her elbows pressed together to trap his head. Rachel also has her legs in a good base
Leaning slightly backward, Rachel drives her knee into Landon's midsection as she drives forward with her hips and pulls his head inward
After she lands, Rachel quickly moves her right hand to the opposite side of Landon's head as she slides her feet clockwise to get a better angle for the next attack.
Rachel underhooks Landon's right arm with her left and pushes Landon's head away with her right. Rachel pulls down on Landon's left shoulder with her underhook to keep Landon in position ( steps 3 & 4 should be done in a quick, fluid manner and Rachel keeps her right leg back)
with her right hand Rachel pulls Landon's head inward as she drives her right knee into his face.