Adjuvants are {HEAD ~ substances} that can be used to nonspecifically augment {TAIL ~ a specific immune response} 
used to nonspecifically augment
Adjuvants are { HEAD ~ substances } that can be used to nonspecifically augment { TAIL ~ a specific immune response }
OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL