u-not do, not be
#u- vb. "not do, not be" (1st pers. aorist uin "I do not, am not"), pa.t. úmë (UGU/UMU). A late (ca. 1968) source gives the forms uin, uin(yë) "I am not", uil(yë) *"you are not", uis "it is not", uilmë *"we are not", uir "are not" and endingless ui *"is not" (VT49:29, 36); these forms were however struck out. The example uin carë "I dont" (PE17:68) combines this negative verb with a following verb in the "simplest aorist infinitive". Compare ua in another late source. See also ui, which (despite its use as an interjection "no") seems to be the endingless 3rd person aorist.
ua-not do, not be
ua- negative verb "not do, not be". If a verb is to be negated, ua (coming before the verb) receives any pronominal endings (and presumably also any endings for plurality or duality, -r or -t), whereas the uninflected tense-stem of the verb follows: With the ending -n for "I", one can thus have constructions like uan carë *"I do not" (aorist), uan carnë *"I did not" (past), uan cára *"I am not doing" (present), uan caruva *"I shall not do" (future). The verb ua- can itself be fully conjugated: #ua aorist (or present?), únë (past), úva "(future), #uië (perfect) (the aorist and perfect are attested only with the ending -n "I"). In "archaic Quenya" these tense-forms could be combined with an uninflected aorist stem, e.g. future *úvan carë = later Quenya uan caruva, "I shall not do". In later Quenya, only the forms ua (present or aorist) and "occasionally" the past tense form #únë were used in normal prose (únen *"I did not, was not"). (PE17:144; compare FS for úva as a future-tense negative verb "will not")