35. The time when or within which anything happens is expressed by
  the ablative without a preposition.  Sec. 275.

  36. 1.  The place at or in which is expressed by the ablative with
    in\.  This answers the question Where?  Before names of towns, small
    islands, and rus\ the preposition is omitted.  Secs. 265, 266.

    2.  Names of towns and small islands, if singular and of the first or
    second declension, and the word domus\ express the _place in which_
    by the locative.  Sec. 268.

Gerund and Gerundive

  37. 1.  The gerund is a verbal noun and is used only in the genitive,
    dative, accusative, and ablative singular.  The constructions of
    these cases are in general the same as those of other nouns.  Sec.
    406.1.

2.  The gerundive is a verbal adjective and must be used instead of gerund + object, excepting in the genitive and in the ablative without a preposition.  Even in these instances the gerundive construction is more usual.  Sec. 406.2.

  38. The accusative of the gerund or gerundive with ad\, or the
  genitive with causa\, is used to express purpose.  Sec. 407.

Moods and Tenses of Verbs

  39. Primary tenses are followed by primary tenses, and secondary by
  secondary.  Sec. 358.

  40. The subjunctive is used in a dependent clause to express the
  purpose of the action in the principal clause.  Sec. 349.

41. A substantive clause of purpose with the subjunctive is used as object with verbs of commanding, urging, asking, persuading, or advising, where in English we should usually have the infinitive.  Sec. 366.

  42. Verbs of fearing are followed by a substantive clause of
  purpose introduced by ut\ (_that not_) or ne:\ (that or lest). 
  Sec. 372.

  43. Consecutive clauses of result are introduced by ut\ or ut
  non\, and have the verb in the subjunctive.  Sec. 385.

  44. Object clauses of result with ut\ or ut non\ are found after
  verbs of effecting or bringing about.  Sec. 386.

  45. A relative clause with the subjunctive is often used to describe
  an antecedent.  This is called the subjunctive of characteristic or
  description.  Sec. 390.

  46. The conjunction cum\ means _when, since_, or _although_.  It is
  followed by the subjunctive unless it means _when_ and its clause
  fixes the time at which the main action took place.  Sec. 396.

  47. When a direct statement becomes indirect, the principal verb is
  changed to the infinitive, and its subject nominative becomes subject
  accusative of the infinitive.  Sec. 416.