Thus, there can be {HEAD ~ an acceptable degree} of {TAIL ~ lapse} in the rotational relationship between the valve disc and the stem 
of
Thus , there can be { HEAD ~ an acceptable degree } of { TAIL ~ lapse } in the rotational relationship between the valve disc and the stem
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH