A blower with a filter is mounted on the outside of the desk and blows {HEAD ~ clean air} into {TAIL ~ the compartment} 
into
A blower with a filter is mounted on the outside of the desk and blows { HEAD ~ clean air } into { TAIL ~ the compartment }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL