Thomason decided to dedicate herself to linguistics and, after spending a year in Germany mastering the language, she was re-awarded the Fellowship and was admitted into Yale University, where she completed both an M.A.
Thomason decise di dedicarsi alla linguistica, e dopo aver studiato la lingua in Germania, ottenne nuovamente la borsa di studio e venne ammessa all'Università di Yale, dove conseguì sia una laurea magistrale