A good way to learn how to keep a rhythm when jumping is to tackle two fences on a circle.
Initially have a pole on the ground eg at B and E in the school so you are working on a 20m circle in the middle of the school.
Trot and then canter over the poles aiming to keep a good rhythm without trying to fiddle and interfere with your horse as you approach the poles.
Then change the poles to two jumps, which can be approached from either way, so that you can do this exercise on both reins.
The jumps need not be very high - the purpose is to keep coming around on the circle, popping each fence with the horse sorting himself out.
All the rider needs to do is concentrate on riding in a good rhythm - and resist the temptation to push the horse out of his rhythm.
When you are happy on both reins in trot, try the exercise in canter, but again, don't try to place your horse at the fence.
All you need to think about is riding a good circle, with a good even rhythm all the way around.
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