Sentence:  The capacity of intellectuals and members of the new professional classes to contribute creatively to national development <WSD>is</WSD> likely to be destroyed by a constraining sense of inferiority toward both their own political class and their colleagues and professional counterparts in the West . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)