dan, lets say you have sidemount and your right knee is close to his waist, ie: on his right side. Put your right knee on his belly and take the arm close to you, if he starts pushing with the far arm and shrimping just jerk his arm towards you and stick your leg inside and you have a triangle, just need to maintain position and get your leg around his neck fully.
The other one is where you have your knee on the belly he pushes with both hands so you switch your knees, ie: you had your right knee on the stomach now you switch and have your left knee on his chest, then you just turn your whole body clockwise while leaving your knee on his chest and you can either land in mount or you can have a triangle, this has to be done fast and it probably won't work on advanced level, but it can be a good surprise move sometimes.
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