DLM short sentence (Distance Learning Methodology), which, briefly, means training without the need to teacher. this method of methods of serious training is that the courses the university also used it.
so, the idea of using this technique in language learning is also very good and can be said of this collection, the educational booklet is the best collection of teaching English is that in the 4 levels of Listening , Speaking , Reading , Writing.
of course, this educational series is appropriate for those who skills good in English language have, because that level of Educational this collection of experts and has been so for beginners-so may not be suitable.