Horwitz summarises findings of SLA research, and applies to L2 teaching some principles of L2 acquisition honed from a vast body of relevant literature.[10] Like Asher, Horwitz highlights the importance of naturalistic experience in L2, promoting listening and reading practice and stressing involvement in lifelike conversations. She explicitly suggests teaching practices based on these principles; ‘[m]uch class time should be devoted to the development of listening and reading abilities’, and ‘[t]eachers should assess student interests and supply appropriate…materials’.[11] The ‘audio-lingual’ teaching practices used in the present study are based on principles explicated by Asher and Horwitz; listening featured heavily, closely followed by reading and speaking practice. The vocabulary items taught were deemed relevant for all learners, regardless of age, and, according to Pfeffer, they are among the most commonly used nouns in everyday German language.[12]