When a pattern says “work” it means to continue in whatever stitch pattern you’ve been doing. In the case of the work in Plantation Lace, the instructions mean to follow the directions given for that lace pattern for 19 rounds.
“Work even” means to continue without shaping, so no increases or decreases.
I think this might be the pattern? http://www.classiceliteyarns.com/pdf/MayfaireCamisole.pdf