11. The block system was not in operation, and communication with adjacent locations was limited. 12. Credo uses the block system , where students study one subject intensively for four weeks. 13. The traditional block systems will remain on these lines despite the installation of CBTC. 14. Then Hiigli set out to organize synergetic geometry into a block system for children. 15. Automatic axle-counting block system ; installation of these systems took place from 1989 to 1993. 16. A primitive if it has no other block systems . 17. Most institutions either use a 7.5, 8, 10, 12, 15 or 20 credit block system . 18. This was called the " absolute block system ". 19. Princeton operates under what is known as the Block scheduling system, specifically the four-block system . 20. The tournament was also divided into a two-block system commonly used in standard wrestling match.
