Semantically, the clause is an “interactive event involving speaker, or writer, and audience” (H & M, p.106). The move in this event is whether we want to initiate or have to respond. This may seem a rather obvious point, that we speak to someone who is listening, but it one that is often overlooked, especially within EFL. Looking at the two sentences below might help demonstrate the importance of this concept of exchange more clearly:
- It is a pen.
- This is a pen.
These two might commonly be found in beginner EFL or young learner texts yet rarely is the difference between them made clear. The first is how you might respond within an exchange to provide new information:
A: What’s that you’ve got there?
B: (It’s) a pen.
This is also evident in written text. The following headline (from www.techcrunch.com) is, in fact, a response to an assumed question on the part of the reader signalled intertextually by a picture which takes the role of initiating the exchange:
Picture: (What’s this?)
Headline: It’s a pen! It’s a bullet! It writes upside down and underwater! It’s a bullet pen!
The second example, however, is how we might initiate an exchange, explicitly drawing attention to the topic of discussion and inviting a response:
Jack: This is an astronaut pen. It writes upside down. They use this in space.
(Seinfeld, S3, E3)
From these two examples we can see that the move of the exchange, whether to initiate or respond, can thus influence the lexico-grammatical choices made within the clause. The choice between it and this is not the result of sentence-level rules but is instead dependent on how the clause functions within the exchange. It also demonstrates the interactive nature of the exchange, that “the speaker adopts for himself a particular speech role, and in doing so assigns to the listener a complementary role which he wishes him to adopt in his turn” (H & M, p.106). The added consequence of this is that the choices available for the response are constrained by those made in the initial move (see also Eggins & Slade, 1997, p.181-2).
There are two types of initiation: open, which is dependent on whether it is an offer, a command, a statement or a question and generally takes the form of a major clause, or a response request, which is the function of the tag question. I think it is important for learners to be aware that the tag question is not just a request for a response, as it is generally presented in textbooks, but it may also function as a request to not respond, to close down the conversation.
There are also two types of response: expected or discretionary. How the two functions of response operate may vary according to nature of the interaction. In the case of an offer, the response may be either one of acceptance or rejection:
Offer: Would you like it?
Acceptance: Yes, please.
Rejection: No, thanks.
Where a demand is made, the response may be either an undertaking or a refusal:
Command: Give it to me!
Undertaking: Here you are.
Refusal: I won’t!
For questions, we may have either an answer or a disclaimer:
Question: What is it?
Answer: A teapot.
Disclaimer: I don’t know.
For statements, there may be either a response or a contradiction:
Statement: He’s giving it to her.
Response: Is he?
Contradiction: No, he isn’t.
(all examples from H & M, p.108)