Watch the Can't You: Ex. 5b online guitar lesson by Andy Aledort from Kings of Blues & Rock Vol. 2: Albert King
This example offers yet another chance to really injure yourself: the entire six-bar phrase requires instantaneous bends of two whole steps followed by increments of either one whole step or a half step. A great exercise is to play these phrases very slowly while attempting to achieve perfect intonation. String-bending and vibrato are essential tools for all blues guitarists, and these phrases will help you master both.