Sentence:  Geometric pottery has not yet received the thorough , detailed study which it deserves , partly because the task <WSD>is</WSD> a mammoth one and partly because some of its local manifestations , as at Argos , are only now coming to light . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)