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     Table of Contents Chapter 19 19.5.2 Irrealis of the present
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Chapter 19: Conjunctive, Conditional and Reported speech

  19.5.2 Irrealis of the present

The Irrealis of the present (Irrealis der Gegenwart) is formed by using the simple conjunctive II in both parts of the sentence. Quite often the conjunctive II is identical to the imperfect and in these cases the conditional (compound conjunctive with the modal verb werden) is used (rule number three). And here again the rule nro three 1/2 applies as well - sometimes the conjunctive II sounds so strange that it is preferable to substitute it with a conditional.

  some examples
I would take him a present if I knew where he lived.
  Ich würde ihm ein Geschenk bringen, wenn ich wüsste, wo er wohnt.
I would buy a car if I had the money.
  Ich kaufte ein Auto, wenn ich Geld hätte.
= The simple conjunctive II is identical with the imperfect => rule number three
Ich würde ein Auto kaufen, wenn ich Geld hätte.

  I would bake a cake if I had flour.
  Ich büke eine Kuchen wenn ich Mehl hätte.
= The conjunctive II does sound very strange. => rule number tree 1/2
Ich würde einen Kuchen backen, wenn ich Mehl hätte.

  I would write him a letter, if I learnt where he lives.

Ich schriebe ihm einen Brief, wenn ich wüsste wo er wohnt.
= Now it is a bit difficult, because both forms do sound a bit weird. Actually both would be a case for rule number three 1/2. But it is not "good style" to use twice the conditional. Probably one would be substituted one would be used as conditional II even though it sounds a bit strange.
a) Ich schriebe ihm einen Brief, wenn ich wissen würde, wo er wohnt.
b) Ich würde ihm einen Brief schreiben, wenn ich wüsste, wo er wohnt.
c) Ich schriebe ihm einen Brief, wenn ich wissen würde, wo er wohnt.
All of the above could be found - the very stylish would even use the "original" version (at least in written form). However to the author the version c) sounds most reasonable.