Applying  Commandment #2 on Interval Memory. The Memory Law of Language “You must always use an effective interval or periodic retrieval memory technique while learning languages”. You can make any language program more effective by applying a high-quality interval memory recall system.  The very best language programs have this system already built in to the structure of the course.  The only way to become fluent in any language is to be able to remember and actually use what you learn.