Sentence:  To reinforce , and sometimes to <WSD>replace</WSD> , 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 was effective over much larger areas . 
Meaning of the word marked with <WSD> tags:  substitute a person or thing for (another that is broken or inefficient or lost or no longer working or yielding what is expected)