The Audio-Lingual Method was developed in the 1950s-1960s and was based on behaviorist theories of language learning. It focused on repetition and drilling of dialogs to make responses automatic. Key principles included using drills to teach dialog lines and repeating the language as accurately and quickly as possible. Techniques included backward build-up drills, dialog memorization, chain drills, multiple-slot substitution drills, transformation drills, and question/answer drills to reinforce sentence patterns through repetition.