TANK---- E Dintro (alternates between and like so):[E-]------|-----------------|[B-]-9s7--|-9p7h9p7h9p7h9p7-|[G-]-9s7--|-9p7h9p7h9p7h9p7-|[D-]-9s7--|-9p7h9p7h9p7h9p7-|