Government and Binding Theory/The pro-drop Parameter

Apart from PRO, which we have seen in the last chapter, there's another type of null subject. For example, in written Finnish, first and second-person subject pronouns are generally omitted (although they are intact in speech):

(1)

The dropping of minä, sinä, me and te is not the same as the dropping of PRO:
 * The dropping is optional.
 * If the resulting null subject were PRO, the PRO theorem would be violated.
 * The resulting null subject is not subject to control.

This led to the introduction of another null subject known as little pro. pro-drop does not apply to all languages though. For example, English and French do not allow it:

(2a) *Is the best professor in the field of theoretical linguistics. (2b) *Est le meilleur professeur dans le domaine de la linguistique théorique.

Rizzi's other properties
Rizzi listed several properties common to pro-drop languages:
 * No pleonastic subjects
 * Subject-VP inversion is possible
 * wh-elements can be extracted more easily in certain situations

Let's examine these properties one by one. Chinese, which is pro-drop, does not have pleonastic subjects, such as the following example in Mandarin:

(3a) Xia yu-le. (Fall rain-asp.) (It has rained.) [Note: It is controversial in linguistics whether 'xia yu' is a word or a phrase, as it has the properties of both. This is irrelevant to the present discussion.] (3b) *Has rained.

Although Italian is primarily SVO, it allows subject-VP inversion, as shown in Rizzi's own example below, while French generally doesn't:

(4a) Ha telefonato Gianni. (has telephoned Gianni) (Gianni has telephoned) (4b) *A téléphoné Jean. (has telephoned Jean) [Note: French allows subject-verb inversions in certain cases like relative clauses, but this is again irrelevant.]