When a request for communication task is detected, the communication apparatus determines whether {HEAD ~ execution} of {TAIL ~ the communication task} can be extended at a later time 
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When a request for communication task is detected , the communication apparatus determines whether { HEAD ~ execution } of { TAIL ~ the communication task } can be extended at a later time
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH