{HEAD ~ The opening} of the exhaust system may also have {TAIL ~ a tubing} to allow the exhaled air to be moved even further away 
have
{ HEAD ~ The opening } of the exhaust system may also have { TAIL ~ a tubing } to allow the exhaled air to be moved even further away
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH