Since the discovery of Chiron , other centaurs have been discovered , and nearly all are currently classified as minor planets , but are being observed for possible cometary behavior .
SCONJ DET NOUN ADP PROPN , ADJ NOUN AUX AUX VERB , CCONJ ADV DET AUX ADV VERB ADP ADJ NOUN , CCONJ AUX AUX VERB ADP ADJ ADJ NOUN .