Regarding Hebrew, I think the trick is to learn the language, but maybe this will help. - https://en.wiktionary.org/wiki/%D7%94%D6%BE
Your verse
the great trials which thine eyes saw, the signs and those great wonders; (Deut. 29:3 JPS)
הַמַּסּוֹת֙ הַגְּדֹלֹ֔ת אֲשֶׁ֥ר רָא֖וּ עֵינֶ֑יךָ הָאֹתֹ֧ת וְהַמֹּפְתִ֛ים הַגְּדֹלִ֖ים הָהֵֽם׃the wondrous feats that you saw with your own eyes, those prodigious signs and marvels. (Deut. 29:2 TNK)
(Deut. 29:2 WTT)
The last four words -
הָאֹתֹ֧ת - the sign(s)
וְהַמֹּפְתִ֛ים - and the wonders
הַגְּדֹלִ֖ים - the great (plural)
הָהֵֽם - the them/those
the initial vav (and) in "and the wonders" separates the last phrase from "the signs". Note how the 1917 JPS -
... the signs and those great wonders
is quite literal while the 1985 edition goes -
... those prodigious signs and marvels
where the last word (the them/those) now also applies to "the signs".
Similarly the noun and adjective combination which starts the sentence is tied together by the definite article appearing in both words.
Probably it's mostly a matter of taste, but it's best to closely look at two good translations in one's native language.
