I notice that there is an all-too-common misconception contained in the question by Sherri Fisher, which was not corrected in Coach Jay's answer.

Whomever wrote the workout meant to prescribe 4 tempo runs of two minutes duration each, with easy running of 1-3 minutes between the runs. But he made the error of saying that there should be 1-3 minutes of easy running "between intervals".

A visit to a library should provide a dictionary that will point out that an "interval" is the time, space, or distance between two things. In other words, the "interval" in the case of the aforementioned workout is the 1-3 minutes of easy running BETWEEN the tempo runs, and not the runs themselves.

This misconception arose years ago by those who originally misunderstood the purpose of interval training - to break a race into segments and gradually SHORTEN THE INTERVALS to approach the race distance under race conditions. It was this training method that produced the first four-minute mile, with Roger Bannister, Chris Chataway, and Chris Brasher running repeat 440's slightly under 60 seconds with increasingly-shorter intervals between.

This training method also has a "down side"; although Bannister set a World Record with his sub-four run on the Isley Road track, it was very quickly bettered by Australia's John Landy, and he never got it back, because his training segments were aimed at slightly under four minutes, which is all that he ever achieved. Although he was one of only three people in the world with sub-four runs when he defeated an injured John Landy in the British Empire and Commonwealth Games mile in 1954, by the time of the 1956 Olympics, he was well down on the All-Time list, and was never a major factor in the 1500m at those Games.