The context of a word governs its meaning of course; but here are some usages of your words in question. There is not much of a mystery here.
τι (ti) is the genitive form of τις (tis) is an interrogative pronoun in direct, indirect, and rhetorical questions meaning “who?” “which (one)?”; “what?” usages include but are not limited to the following:
- In questions to which the answer “nobody” is expected
- Who? In the sense of what sort of (a) person?
- Who are you? What sort of man are you?
- Which of two?
- Why? For what reason?
- Why? For what purpose?
- With what? through whom?
- Because of what thing?
- In exclamation “how?”
πῶς (pos) as an interrogative, particle means how? In what way? In direct questions a. to determine how something is happening, or should happen; w. indicative how? or in what?
b. in questioning indicating surprise “how is it possible that?”; or “I do not understand how”; a series of questions expressing surprise, introduced again and again by Πως. E.g. how is it possible you do not understand me? (Mt 16:11; Mk 8:21); “how is it you have no faith?” (Mk 4:40; Mt 21:20).
c. in questions denoting disapproval or rejection “with what right?”; “how dare you?”; how is it that you are bold enough to come in here?”; “how can you say?”
d. in rhetorical questions that call an assumption into question or reject it altogether “how (could or should)?
e. in questions of deliberation with deliberative subjunctive “what comparison can we find in the kingdom?” (Mk 4:30); “how are you to escape? = “you will not escape at all” (Mt. 23:33).
- In direct questions—a. with indicative after verbs of knowing, saying, asking, etc. In exclamation “how. . . !”
Walter Bauer, et. al. A Greek English Lexicon of the New Testament, The University of Chicago Press, 1979.
Wesley J. Perschbacher, The Analytical Greek Lexicon, Hendrickson Publishers, 1990.
Bernard Taylor, Analytical Lexicon to the Septuagint, Hendrickson Publishers, 2010.