Sentence:  The Healing brush is similar to the Clone Stamp in that information is <WSD>sampled</WSD> by Alt-clicking and then painted into other parts of the image. The big difference is that the Healing brush attempts to make the <WSD>sampled</WSD> data match the lighting and shading of the area to which it's being applied. 
Meaning of the word marked with <WSD> tags:  To take or to test a sample or samples of.