OET interlinear JOS 23:13

uW Translation Notes:

Note 1 topic: figures-of-speech / reduplication

יָד֨וֹעַ֙ תֵּֽדְע֔וּ

to_be_sure you(pl)_be_sure

Joshua is repeating forms of the verb know in order to intensify the idea that it expresses. If your language can repeat words for intensification, it would be appropriate to do that here in your translation. If not, your language may have another way of expressing the emphasis. Alternate translation: [you may know for certain]

Note 2 topic: figures-of-speech / metaphor

וְ⁠הָי֨וּ לָ⁠כֶ֜ם לְ⁠פַ֣ח וּ⁠לְ⁠מוֹקֵ֗שׁ וּ⁠לְ⁠שֹׁטֵ֤ט בְּ⁠צִדֵּי⁠כֶם֙ וְ⁠לִ⁠צְנִנִ֣ים בְּ⁠עֵינֵי⁠כֶ֔ם

and=they_will_be to/for=you(pl) as,snare and,as,trap and,as,whip in/on/at/with,sides_of,your(pl) and,as,thorns in/on/at/with,eyes_of,your(pl)

Joshua is speaking as if these nations would actually become a trap, snare, whip, and thorns. If it would be clearer in your language, you could express these as comparisons. The UST models one way to do that. You could also state the meaning plainly. Alternate translation: [And they will harm you in many different ways]