The bilingual method, however, advocates two revolutionary principles based on the results of scientifically controlled experiments in primary and secondary schools. In contrast to the audiovisual method and the direct method, the printed text is made available from the very beginning and presented simultaneously with the spoken sentence to allow learners to see the shape of individual words. Also, from the outset meanings are conveyed bilingually as utterance equivalents in the manner of the sandwich technique, thus avoiding meaningless and hence tedious parroting of the learning input.