Qenya
tá
adverb. then, at that time (past now)
ta
pronoun. it (3rd sg. inanimate)
en ye tá
that is a tee
tan(an)
adverb. then, at that time (past now)
There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.
Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.
The correlatives tanan or (archaic) †tan “then, at that time” appearing in Demonstrative, Relative, and Correlative Stems (DRC) from 1948 (PE23/109), a combination of ᴹQ. ta “that” and ᴹQ. -n(an) “time”.