Sentence:  Dr. Isaacs <WSD>was</WSD> so pleased with the quality of her biographical study of Sara Sullam that he considered submitting it to the Century Magazine or Harper 's but he decided that its Jewish subject probably would not interest them and published it in The Messenger , `` so our readers will be benefited instead '' . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)