Sentence:  bursting from the <WSD>lips</WSD> of a charging cavalry trooper was the last sound heard on this earth by untold numbers of Cheyennes , Sioux and Apaches , Mexican banditos under Pancho Villa , Japanese in the South Pacific , and Chinese and North Korean Communists in Korea . 
Meaning of the word marked with <WSD> tags:  either of two fleshy folds of tissue that surround the mouth and play a role in speaking