key of E e a e b e[--------------------------------------------------------] b[--------------------------------------------------------] g[-------------------6------------------------------------] d[--------6-----7-7h9--9-7-------6------------------------] a[--7-7h9---9-7------------7-7h9---9-7--------------------] e[-------------------------------------7------------------] e a e b e[--------------------------------------------------------] b[--------------------------------------------------------] g[--------------------6-----------------------------------] d[--------6-----7-7h9---9-7---7-7h9-----------------------] a[--7-7h9---9-7-------------7-----------------------------] e[--------------------------------------------------------]