The main constituent order of a language has often been treated as a major typological parameter. If it is rigid, it does characterize the independent declarative clause of a language. German has a verb-second rule which says: In the constituent structure of an independent declarative clause, the finite verb takes the second position. In the topology of the German sentence, the position preceding the finite verb is called the forefield. Thus, the forefield makes room for exactly one constituent ().

is from colloquial German. In this variety, modal particles abound, including the intranslatable ja (obvious) in f. The anaphoric proform da is the first component of the univerbated prepositional phrase dafür in . Given that it is necessarily thematic in such a context, this prepositional complex naturally occupies the forefield of the clause (a).

Preposition stranding is possible in colloquial German (not in the standard). In #b, only the anaphoric proform is fronted while the preposition is left in situ, i.e. where it is in .

Quite generally, instantly taking up what immediately precedes in discourse does not require any overt means; short-distance anaphora of such thematic material may be zero and is, in fact, zero in many languages. In colloquial German (not in the standard), the introductory anaphoric proform is therefore often omitted. This produces the variant c.

In colloquial German, the forms of the anaphoric demonstrative in initial position are most easily dropped if they have inanimate reference. Thus, the neuter form das is also often omitted ().

Now the omission of the introductory proform is a decisive step: If the forefield of the clause is not occupied, the result is a verb-initial construction. The norm does not allow verb-initial independent declarative clauses.¹ This is, however, the way that they get into the language at the colloquial level.

This change of main constituent order follows a set of principles:

1. Rule of syntax: In a verb-second clause, the forefield contains one constituent.
2. Principle of information structure: The forefield may be occupied by thematic material.
3. Principle of coding: The element of highest thematicity may be elliptical.

The conclusion is that the change from verb-second to verb-first order in colloquial German is not a direct violation of a rule of syntax. In no phase is the finite verb simply put directly after the clause boundary. Instead, the change is a natural consequence of the interplay of independent principles at work in language.

A rather similar phenomenon is observed in the recent history of Mandarin: A neutral demonstrative serving as a dummy complement of a coverb is omissible. If it is omitted, the syntax of the construction changes. This is treated in the section on the Chinese progressive construction.

¹ To be precise, there is one exception to this: The standard language provides for the construction for independent causal clauses which start by the finite verb obligatorily followed by the modal particle doch (cntrdct). This construction is not directly related to the one at issue above.

Reference

Auer, J.C. Peter 1991, "Zur Verbspitzenstellung im Gesprochenen Deutsch." Deutsche Sprache 3:193-222.