In addition to the memory, {HEAD ~ the system} includes a write module and a read module, each of which is coupled to {TAIL ~ the memory} 
In addition to the memory , { HEAD ~ the system } includes a write module and a read module , each of which is coupled to { TAIL ~ the memory }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL