Sentence:  Those persons who were lucky enough to see and hear the performance of his work at the Brest-Silevniov Festival in August , 1916 , will certainly welcome his return to public notice ; and it is not unlikely that , even as the great Bach lay dormant for so <WSD>many</WSD> years , so has the erudite , ingenious SalFininistas passed through his `` purgatory '' of neglect . 
Meaning of the word marked with <WSD> tags:  a quantifier that can be used with count nouns and is often preceded by `as' or `too' or `so' or `that'; amounting to a large but indefinite number