Another Option
This week we will be doing a cut-down workout. The distances of the intervals will be 400-800-400-800-400. Each 400 of the workout (including both 400s of the 800) you need to get faster with your last 400 being the fastest. Try to drop 2-3 seconds each time. For example: if you start with a 2-minute 400 the next 800 should 3:54 (1:58/156), followed by a 1:54 for the next 400, then a 3:42 (1:52/1:50) 800, and finally a 1:48 400. The workout teaches you control and to shift pace during a run.
Hope it makes sense. Enjoy
P.S. We recently tested the defibrillators at my workplace. Of course they didn't work, no one was shocked.