I agree with the spirit of Fiasco Labs' answer.  But the truth is that if a valve is almost off (just a few drips) then careful "snugging" via a pair of channel-locks is the first thing your plumber would try.  And it'll work... 61.4 percent of the time.
Ok, it's not that scientific.  But in my experience it'll work slightly more often than not.

But if a good snugging doesn't help, then give up.  Don't go for herculean twisting.  That's when you make a bad situation worse.

How do I force a tight globe-valve water shutoff to fully close?
Is it possible to use the 2D camera, but just for a part of the screen? Perhaps I want some info on the screen about score and other things, but I want that at a fixed place, just like when not using a 2D camera?
