a.  Instead of the Indicative, Livy and subsequent writers employ the
  Subjunctive of the Historical tenses in the Protasis to denote repeated
  action; as,—­

    si dicendo quis diem eximeret, if (ever) anybody consumed a day in
    pleading; si quando adsideret, if ever he sat by.

4.  Where the sense demands it, the Apodosis in conditional sentences of the First Type may be an Imperative or one of the Independent Subjunctives (Hortatory, Deliberative, etc.); as,—­

    si hoc creditis, tacete, if you believe this, be silent;

    si hoc credimus, taceamus, if we believe this, let us keep silent.

Second Type.—­’Should’-’Would’ Conditions.

303.  Here we regularly have the Subjunctive (of the Present or Perfect tense) in both Protasis and Apodosis; as,—­

    si hoc dicas, erres, or si hoc dixeris, erraveris, if you should say
    this, you would be mistaken;

    si velim Hannibalis proelia omnia describere, dies me deficiat, if I
    should wish to describe all the battles of Hannibal, time would fail
    me;

    mentiar, si negem, I should lie, if I should deny it;

    haec si tecum patria loquatur, nonne impetrare debeat, if your country
    should plead thus with you, would she not deserve to obtain her
    request?

  a.  The Subjunctive in the Apodosis of conditional sentences of this type
  is of the Potential variety.

  b.  Sometimes we find the Indicative in the Apodosis of sentences of the
  Second Type, where the writer wishes to assert the accomplishment of a
  result more positively; as,—­

    aliter si faciat, nullam habet auctoritatem, if he should do
    otherwise, he has no authority.

Third Type.—­Supposed Case Represented as Contrary to Fact.

304. 1.  Here we regularly have the Subjunctive in both Protasis and Apodosis, the Imperfect referring to present time, and the Pluperfect referring to past; as,—­

    si amici mei adessent, opis non indigerem, if my friends were here, I
    should not lack assistance;

    si hoc dixisses, errasses, if you had said this, you would have
    erred;

    sapientia non expeteretur, si nihil efficeret, philosophy would not be
    desired, if it accomplished nothing;

consilium, ratio, sententia nisi essent in senibus, non summum consilium majores nostri appellassent senatum, unless deliberation, reason, and wisdom existed in old men, our ancestors would not have called their highest deliberative body a senate.

2.  Sometimes the Imperfect Subjunctive is found referring to the past, especially to denote a continued act, or a state of things still existing; as,—­