After passage through {HEAD ~ the water}, {TAIL ~ the air} is fed into the interior of the indoor institution 
After passage through { HEAD ~ the water } , { TAIL ~ the air } is fed into the interior of the indoor institution
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH