18.4.1. La oración subordinada: Oración sujeto, de complemento directo o preposicional

 The subordinate clause: Subject clause, direct object clause or prepositional clause
Most subordinate clauses act as subjects, direct or prepositional objects. The conjunction used for this type of subordinate clause is that in English and dass in German.
 Subject clauses
The subject clause occupies the place of the subject in a main clause. Often, the pronoun es1) appears optionally in the main clause, where it already indicates the subordinate clause. This pronoun must appear in the first position of the main clause whenever this position is not occupied by another element:
 
Main clauseSubordinate clause
functioning as subject
 english
1stpos.2ndpos.
verb
 objects
 Mir gefällt (es) sehr, dass Sie kommen. I am very pleased that you are coming.
 Es gefällt  mir sehr, dass Sie kommen. I am very pleased that you are coming.
 Mich freut (es),  dass du gekommen bist. I'm glad (that) you came.
 Es freut  mich, dass du gekommen bist. I'm glad (that) you came.
 Es war  mir wichtig,  dass er gekommen ist. It was important to me that he came.
 Mir war (es) wichtig, dass er gekommen ist. It was important to me that he came.
 Wichtig war (es) mir, dass er gekommen ist. It was important to me that he came.
 
If the subordinate clause precedes the main clause, in English, the conjunction generally becomes the fact that (1). In German, die Tatsache, dass or simply dass can be used in this case. In this case, the pronoun es cannot be used to refer to the subordinate clause:
 
   (1) Die Tatsache, dass Sie kommen, gefällt mir sehr.
    That fact that you are coming pleases me very much.
   (2) Dass Sie kommen, gefällt mir sehr.
    I am very pleased that you are coming.
 
 Direct object clauses
If the subordinate clause functions as a direct object (Akkusativobjekt), the pronoun es1)referring to the subordinate clause is uncommon but possible. It is almost always optional and should never be in the first position of the main clause:
 
Main clauseSubordinate clause
functioning as direct object
 english
1stpos.2ndpos.
verb
 objects
 Ich sehe  (es),   dass du arbeitest. I see that you are working.
 Ich finde  (es) gut, dass du kommst. I think it's good that you come.
 Er glaubt  (es) ihr, dass sie damit nichts zu tun hat. He believes her that she has
 nothing to do with it.
 
 Subordinate clause functioning as a prepositional object
If the subordinate clause functions as a prepositional complement, the pronominal adverb corresponding to the preposition governing the verb must appear, with its structure da(r) + preposition (Korrelat) already indicating the subordinate clause in the main clause. This also applies if the subordinate clause depends on a verbal phrase that requires a preposition:
 
Main clauseSubordinate clause functioning
as aprepositional object
 español
 subj. + verb 1 objects  last pos.
verb 2
 Er erinnert die Schüler daran,    dass bald Ferien sind. He reminds the pupils that the
 holidays are coming soon.
 Sie tragen viel dazu bei,  dass die Stadt sauber ist. They contribute a lot to keeping
  the city clean.
 Er hat  darauf gewartet,  dass der Bus kommt. He has been waiting for the
  bus to arrive.
 
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 1) Incidentally, the German technical term for the use of es in this sense is Korrelat..