The first extension of meaning is that concerned with the attitute of the speaker to the content being expressed. This is minimally necessary in order to motivate control of variation such as the following based on the sentence ``She studied art in 1916 - 1919 with Brandenburg'' from the example texts:
| (a) | Did she study art with Brandenburg in 1916--1919? |
| (b) | She studied art with Brandenburg in 1916--1919, didn't she? |
| (c) | Actually, she studied art with Brandenburg in 1916--1919. |
Here, sentence (a) changes the speech function of the sentence to a query; sentence (b) changes the speech function to request support from the hearer; and sentence (c) introduces more content, but here that information reflects the speaker's speech act force. In systems for spoken generation, there is also the further variation:
| (d) | She studied art with Brandenburg in 1916--1919? |
In (d), the sentence structure is as for an assertion, but the intonation selected indicates a question; there are several accounts of intonation in generation (cf. [Fawcett: 1990,Prevost and Steedman: 1994,Abb, Günther, Herweg, Lebeth, Maienborn and Schopp: 1996,Grote, Hagen and Teich: 1996]). Sources of control for lexicogrammars must then include provision for such speech functional variation. In order to constrain a lexicogrammar to produce declarative sentences similar to those of the example texts, the skeletal input of Figure 1 must include at least the additional information:
:speech-act (sa / assertion)
Further additions would be responsible for the control of interpersonal adjuncts as used in (c), interactional tags such as in (b), etc.
Interpersonal meanings can also have a decisive influence on other aspects of a text. For example, expressions of various speaker attitudes will partially determine the most appropriate words selected (`artist' vs. `charlatan'; `artwork' vs. `junk'). When generation systems have access to words varying in this way (which they increasingly do due to the re-use of large-scale lexicons; cf. [Knight and Hatzivassiloglou: 1995]), they need to make sure that they do not select inappropriately. Interpersonal force is also important for the correct realization of requests, orders, statements, etc.; this can have substantial consequences for grammatical selections as well as word selections (cf. [Hovy: 1988a,Kume, Sato and Yoshimoto: 1989]).