{HEAD ~ Suitable means} include, but are not limited to, the periodic addition of base to {TAIL ~ the aqueous solution} or the use of buffers 
{ HEAD ~ Suitable means } include , but are not limited to , the periodic addition of base to { TAIL ~ the aqueous solution } or the use of buffers
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH