These may result in extreme horizontal-branch stars ( subdwarf B stars ) , hydrogen deficient post-asymptotic-giant-branch stars , variable planetary nebula central stars , and R Coronae Borealis variables .
DET AUX VERB ADP ADJ ADJ NOUN ( NOUN NOUN NOUN ) , NOUN ADJ NOUN NOUN , ADJ ADJ NOUN ADJ NOUN , CCONJ NOUN PROPN PROPN NOUN .