Sentence:  With a large and circumspect 20 th Century technique , he wove the materials of national heroes and events , national folklore and children 's fairy tales - Slavic dances and love songs - into a solid musical literature which <WSD>served</WSD> his people well , and is providing much enjoyment to the World at large . 
Meaning of the word marked with <WSD> tags:  devote (part of) one's life or efforts to, as of countries, institutions, or ideas