Ok I'll bite. How many times have you replaced the tube? Did you find the hole in the bad tubes? Is the hole in the same place on all the punctured tubes? Trying lining up the valve stem with the valve stem hole in your wheel and using it to find the general location on your wheel/tire where you keep getting a puncture to see if you can find it. Could be something sharp in the tire, a slit in the tire, a whole in the rim tape, or a sharp edge in the metal on the wheel.