Grammar♦Many adverbs are formed from 1 st/2nd- declension adjectives by adding ē to the adjective stem.
Grammar♦Many adverbs are formed from 3rd- declension adjectives by adding iter to the adjective stem.
Grammar♦Some adverbs use the neuter accusative singular form of the adjective as an adverb.facile multum
Grammar♦Duo is declined only in the plural. (Notice M/N in first column, not M/F)
Grammar M/N F duo duae duorum duarum duobus duabusduo (also m. duos) duas duobus duabus
Grammar♦Tres tria is declined like the plural of brevis –e.
Grammar M/F N tres triatrium triumtribus tribus tres triatribus tribus
Grammar♦Centum, one hundred, and mille, one thousand, are indeclinable.
Grammar Cardinal Ordinalunus –a –um one primus –a –um firstduo –ae –o two secundus –a –um second tres tria three tertius –a –um third quattuor four quartus –a –um fourth quinque five quintus –a –um fifth sex six sextus –a –um sixth septem seven septimus –a –um seventh octo eight octavus –a –um eighth novem nine nonus –a –um ninth decem ten decimus –a –um tenth
GrammarRoman Numeral Cardinal XI undecim eleven XII duodecim twelve XIII tredecim thirteen XIV quattuordecim fourteen XV quindecim fifteen XVI sedecim sixteen XVII septendecim seventeen XVIII duodevigenti eighteen XIX undevigenti nineteen XX viginti twenty