Halliday's metafunctions are ideational, interpersonal and:

1. In systemic functional linguistics all languages involve three metafunctions at once. 2. The ideational metafunction construes experience of reality. 3. The interpersonal metafunction enacts social relations. 4. The third weaves these two together to create text, so it is called textual. 5. Phatic, poetic and conative are from Jakobson's list, not Halliday's metafunctions. 6. So the third metafunction is textual. **Why the other options fail:** - Phatic is a Jakobson function of keeping contact. - Poetic is a Jakobson function of focusing on the message itself. - Conative is a Jakobson function of directing the listener. _Source: Wikipedia, "Systemic functional linguistics", section "introduction" (revision 1343758540)_