How can i share a sketch to generate 2 parts ? To modify the sketch and both parts update.

How can i share a sketch to generate 2 parts ? To modify the sketch and both parts update.

I do a sketch and with it i do a part,  but with the same sketch do other parts,  actually y copy the sketch,  but sometimes if i modify the sketch i forget update the others copies, and it produce a error on the production.

SolidworksParts And Features