open up notepad and write down titletext ["hey moron",PLAIN DOWN]
then choose save and click on Text documents. Change that to All documents and call the filename chat.sqs
now, ingame type [] exec "chat.sqs" when you want this to happen. I.e. in a trigger activated by west, at on activation.
if you want them to say more an wait 3 secs between each line, type
titletext ["hey moron",PLAIN DOWN]
~3
titletext ["hey monkey",PLAIN DOWN]
~3
so, if you want them to wait a whole minute you type ~60
got the picture?