In the present example, {HEAD ~ the gate structures} interpose {TAIL ~ LDD features} respectively disposed in the source region and the drain region 
interpose
In the present example , { HEAD ~ the gate structures } interpose { TAIL ~ LDD features } respectively disposed in the source region and the drain region
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH