In the m(number)sdi.mfk file, it usually looks like this
AddStage(0);
AllowMissionAbort("false");
AddObjective("dialogue");
AmbientAnimationRandomize( 1, 0 ); // ( pc=0, npc=1) (nonrandom=0, random=1)
AmbientAnimationRandomize( 0, 0 );
AddAmbientNpcAnimation( "dialogue_cross_arms" );
AddAmbientNpcAnimation( "none" );
AddAmbientPcAnimation( "none" );
AddAmbientPcAnimation( "dialogue_hands_in_air" );
SetPresentationBitmap( "art/frontend/dynaload/images/mis01_03.p3d" );
SetDialogueInfo("homer","marge","scorpion",0);
CloseObjective();
CloseStage();