Art superstar Sherrie Levine made a name for herself in the 1970s and ’80s as part of the “Pictures Generation” and appropriationist movements. Essentially, she has based her career on reproducing and recontextualizing the work of other artists, and the Portland Art Museum’s exhibition of her work illustrates this tactic well. On display are two vintage Levine pieces and three that were made during the past two years. But the pièce de résistance is a series of 16 paintings riffing on Claude Monet’s famous and ubiquitous Water Lilies. Viewers unfamiliar with Levine will benefit from this thoughtfully conceived introduction. Through Oct. 13.