7. Tiryntha. This is a Greek accusative form. See the note on _aera_,
4, 11.

10. Duodecim annos, accusative of duration of time.

11. Eurystheo. The English verb 'serve' is transitive, but _servio_ ('be
subject to') is intransitive and takes an indirect object.

14. quae. See the note on line 1. What is the case of quae?

16. Primum is chiefly used in enumeration, primo (line 6) in contrasting
an action or state with one that follows it.

19. secum. The preposition _cum_ follows and is joined to the reflexive
and personal pronouns, usually also to the relative pronoun.

22. neque enim. See the note on 7, 12.

26. respirandi, the genitive of the gerund. It modifies facultas. The
gerund corresponds to the English verbal noun in _-ing_.

13. 5. Hoc. We might expect _haec_ referring to Hydram, but a
demonstrative pronoun is commonly attracted into the gender of the
predicate noun (here monstrum).

cui erant, 'which had,' literally 'to which there were.' This
construction is found only with _sum_. It is called the dative of
possession.