Although motor 68 can drive {HEAD ~ elongate member} 30 by {TAIL ~ any conventional means}, a gear system 70 is preferably used 
by
Although motor 68 can drive { HEAD ~ elongate member } 30 by { TAIL ~ any conventional means } , a gear system 70 is preferably used
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH