An interactive fiction by Juhana Leinonen (2008) - the Inform 7 source text
Carry out babbling to the guard that:
say "[one of][g]I do not UNDERSTAND you!' the guard shouts.[or][g]SPEAK UP!' the guard shouts.[or][g]WHAT?' the guard shouts.[or]Nothing particular about that topic comes to mind.[or]You're about to ask, but you're not sure how to word the question.[at random]";
now the guard is interested.