Subjunctive II (Conditional)

This subjunctive mood is used to make statements that are contrary to fact, instead of factual statements that are made in the indicative mood.  There are two forms of the German subjunctive: Subjunctive II and Subjunctive I.  Subjunctive II or the general subjunctive is used with if...then (wenn... dann) statements and conditional sentences.  Subjunctive I or special subjunctive is a less common mood that is used with indirect discourse.

The present tense of Subjunctive II is derived from the imperfect tense of the indicative.  For weak (regular) verbs, the subjunctive II is identical to the imperfect tense.  For strong (irregular) verbs, the present tense of the subjunctive II takes the past tense stem of the imperfect, adds an umlaut where possible, and adds the following endings:

Some exceptions include:

The past tense of Subjunctive II is derived from the past perfect tense of the indicative.  It is composed of a form of the subjunctive of sein or haben and a past participle.

Conditional sentences
These sentences are based on an if... then (wenn... dann) pattern in both English and German.  Dann can be omitted in these sentences also.  Remember that wenn is a subordinating conjunction, and forces the conjugated verb to the end of the clause.

Present Subj. II:  Wenn ich Zeit hätte, (dann) ginge ich ins Kino.  If I had time, (then) I would go to the movies.
Past Subj. II:  Wenn ich Zeit gehabt hätte, dann wäre ich ins Kino gegangen.  If I had had time, (then) I would have gone to the movies.

Wenn clauses may be introduced by a verb, and in this case, wenn disappears and dann may be replaced by so.

Kommt er heute nicht, (so) kommt er morgen.  If he's not coming today, then he'll come tomorrow.

A conditional sentence may begin with the dann clause as well; but dann is never used and the clause uses normal word order.

Wir trinken den Kaffee nicht, wenn er zu heiß ist.  We don't drink coffee if it is too hot.

Forms of würden + an infinitive
Würde and an infinitive translate to would + infinitive and is more common than the one word form in the dann clause.  Wenn clauses tend to avoid the würde construction, except with these eight verbs: helfen, stehen, sterben, werfen, brennen, kennen, nennen, and rennen.  These eight verbs use the würde construction in the wenn clause because the one word forms are archaic.  Moreover, conversational German tends to replace many subjunctive II forms of strong verbs with the würde construction.  However, this construction cannot be used with modal auxiliaries, haben or sein.