18.6 Putting it together in an example

Consider the sentence:

die Frau liebt der Mann

It is clear that ``der Mann'' must be the subject and ``die Frau'' the accusative object, but how does constraint propagation derive this conclusion.

1. ``liebt'' must be the root of the sentence since it is the only finite verb.

2. ``der'' cannot be the determiner for ``Frau'' since it comes after it.

   1. therefore ``Mann'' is the only possible head for ``der''.

   2. as a consequence, ``Mann'' cannot also be head of ``die''.

   3. thus, only ``Frau'' can be head of ``die''.

3. due to the agreement constraint, ``der Mann'' must be nominative:

   1. therefore ``Mann'' cannot be the accusative object of ``liebt''.

   2. the only role left for ``Mann'' is to be subject of ``liebt''.

   3. therefore, the only role left for ``Frau'' is to be object of ``liebt''.