Is Tennyson's poem "Lady of Shalott" still copyrighted or is it now public domain?

I want to quote a few stanzas from Lady of Shalott by Tennyson in my novel, as one student reads it out loud and the other student admires her as she reads it. I just want to make sure I don't get sued by some Tennyson estate. I've experienced the backlash of borrowing something still copyrighted and trademarked.