Sentence:  To reinforce , and sometimes to replace , the simulated typography , Braque and Picasso began to mix sand and other foreign substances with their paint ; the granular texture thus created likewise called attention to the reality of the surface and <WSD>was</WSD> effective over much larger areas . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)