Sentence:  Hendricks had Billy Mitchell , tenor sax ; Pony Poindexter , alto sax ; Jimmy Witherspoon , blues singer ( and a good one ) , and the Ike Isaacs Trio , which has <WSD>done</WSD> such wonderful work for two afternoons now , helping him with the musical examples . 
Meaning of the word marked with <WSD> tags:  carry out or perform an action