In her new trio “And How Should I Begin?,” the gifted young choreographer struggles with T. S. Eliot’s “The Love Song of J. Alfred Prufrock.” The poem is both muttered sotto voce and recited outright, and Vandenbroucke draws upon its teacups, sprawled bodies, magic lanterns, and mermaids riding the waves. Yet the dance, measured out in super-brief vignettes, is strongest when it treats the poem’s melancholy obliquely, using photocopies of the poem to wall off or connect the dancers.