Sentence:  Although the play does show a certain structural amateurishness ( there are eleven acts varying in length from twenty-five seconds to an hour and a half ) , the statement it makes concerning the ceaseless yearning and searching of youth <WSD>is</WSD> profound and worthy of our attention . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)