15. opus. Compare this word with operae and labore, line 12. _Labor_ is
used of heavy or exhausting labor, _opera_ of voluntary exertion or
effort, _opus_ of that upon which one labors or of the completed work.

17. imperaverat. This verb takes an indirect object to express the person
ordered (ei). The action commanded is expressed by the subjunctive in a
clause introduced by _ut_ and used as the object of _impero_ (ut
necaret). Notice that this may be translated 'that he should kill' or 'to
kill.' Compare now the construction with _iubeo_, 13, 22, with which the
command is expressed by the accusative and infinitive (_Herculem
referre_).

19. carne. _Vescor_ is an intransitive verb and governs the ablative.

22. appropinquandi. See the note on 12, 26.

23. constitit, from _consto_. Compare 15, 10.

pedibus, 'on foot,' literally 'by his feet.'

25. consumpsisset. The imperfect and pluperfect tenses of the subjunctive
are used with cum, 'when,' to describe the circumstances of the action of
the main verb. Compare 14, 20, and the note.

26. hoc conatu. See the note on 13, 11.

27. peteret. The subjunctive is used with ut to express purpose. The best
translation is usually the infinitive ('to ask'), but the Latin
infinitive is not used in model prose to express purpose.