Therefore, the grass can be mown, without leaving {HEAD ~ any uncut grasses}, so as to have {TAIL ~ a good finish} 
Therefore , the grass can be mown , without leaving { HEAD ~ any uncut grasses } , so as to have { TAIL ~ a good finish }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL