How to filter out part-of-speech tag?

var sentence = "/`` Do/VBP n't/RB cut/VB off/RP its/PRP$ power/NN ,/, "/'' he/PRP said/VBD ./. ;
var pattern = new Regex(@"/(?:[.,]|\p{Lu}+\b)");
var outcome = pattern.Replace(sentence, string.Empty);

//Output : "/`` Do n't cut off its$ power , "/'' he said .

How should I modify the pattern to produce expected output of:

"Don't cut off its power," he said.