Career
She began studying French and German language at the University of Copenhagen in 1929. She specialized in linguistics and her thesis treated "the importance of dialect geography for the perception of sound changes."
Tired of the theoretical discussions of Hjelmslev"s circle, she took up research in the field of phonetics in which she became an international figure, publishing widely used text books about general phonetics and phonological theory. During the German occupation of Denmark from 1940-1945, she worked in the resistance group of Professor Carsten Høeg and under great risk helped him assemble a list of Danish nazis to be prosecuted after the liberation.