[coffeebean]

How do I use the water shut off valves which are under the sinks, at the water source for the toilets, the refrigerator, etc? Turning those white knobs left to right or right to left seems to do nothing. I have tried to pull out the knobs towards me but they won't budge and I'm afraid of breaking something. I have to do a plumbing repair to my kitchen faucet and I really don't want to have to turn off the main water valve for the whole house. How do these interior shut off valves work? Thanks