Both hands are in "F" handshapes. Use an alternating forward and back motion. As you slide one hand forward, slide the other backward. Repeat a couple times. The hands do not go up and down, just forward and back.
EXPLAIN:
Sample sentence: Can you explain algebra to me? = ALGEBRA CAN YOU EXPLAIN ME?
Notes:
If you move your hands ("F" handshapes) up and down alternately it means "judge/court/if."
Notes: