If {TAIL ~ exposure} of {HEAD ~ all the pattern portions} were not successfully completed, processing returns to the step at which the error occurred and repeated 
If { TAIL ~ exposure } of { HEAD ~ all the pattern portions } were not successfully completed , processing returns to the step at which the error occurred and repeated
OTH TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH