Sentence:  On some level, the filmmakers behind Monster Trucks must have recognized the ill fit of Till playing a teenager, because they cast Jane Levy, a 27-year-old who can pass for younger but not a decade younger, as Meredith, a nerdy classmate of Tripp's who <WSD>moons</WSD> over him as she insists on making an appointment to tutor him in biology. 
Meaning of the word marked with <WSD> tags:  ("usually followed by" '''over''' "or" '''after''') To fuss over something adoringly; to be infatuated with someone.