17. volébant, dedit. Consider the tenses. Each army waited for some time for the other to cross; finally Hercules gave the signal.
22. occíderint. The perfect subjunctive is sometimes used in result clauses after a past tense in the principal clause. This is contrary to the general principle of the sequence of tenses, which requires the imperfect or pluperfect subjunctive after a past tense, the present or perfect subjunctive after a present or future tense.
23. Virí. Compare this with hominibus, 12, 2.
24. praestábant. Compare the tense with praestitérunt, line 21.
27. neu. As neque or nec is used for 'and not,' so néve or neu for 'and that not' in an object-clause or a clause of purpose.
20. 1. quibus, 'and by these,' The relative is much used in Latin to connect a new sentence with the one preceding. When so used, it is generally best rendered by 'and' or 'but' and a demonstrative or personal pronoun.
ita … ut. See the note on 17, 9.
2. essent, most easily explained as the subjunctive of attraction. By this is meant that the verb is attracted into the mood of the clause upon which it depends.
4. púgnátum est, 'the battle raged' or 'they fought,' literally 'it was fought,' Intransitive verbs are often thus used impersonally in the passive, with the subject implied in the verb itself, as púgnátum est = púgna púgnáta est.
11. aestátis, partitive genitive. Notice that multum is used as a noun.