Priusquam inde digrederentur, Tullus Mettio imperat uti iuventutem in armis habeat: ‘se eorum opera usurum [usurum esse], si bellum cum Veientibus foret [foret = esset].’ Ita exercitus inde domum abducti sunt.
Before they departed, Tullus commanded Mettius to keep his youth under arms: so as to be of use in defending their freedom, should war occur with the Veienii. in this way the army was led home from there.
se eorum opera usurum . . . – "[Tullius said] he would use their work/efforts . . . " Not sure where you get “defending their freedom”
ita exercitus inde domum abducti sunt – “Thus, the armies were led home from there.” Note the plural.
'se eorum opera usurum . . . – "[Tullius said] he would use their work/efforts . . . " Not sure where you get “defending their freedom”
ita exercitus inde domum abducti sunt – “Thus, the armies were led home from there.” Note the plural.’
I spent a while figuring out that Opera wasn’t plural but was ablative singular, - thinking maybe ‘se’ was ablative in some way following usurum… then another few minutes figuring out (or not) who ‘se’ was referring to. ..and then I looked up a definition of Opera in L&S and one of the definitions said ‘freedom’…
…a catalogue of errors.
Plural exercitus noted.
as ever thanks for your guidance…
“Service” might be a better rendering of opera here.