Here is an example code for displaying sentence char by char :
Code:

---

var i;
STRING tempString1;
STRING tempString2;
STRING sentence = "Hello, World!!";

text showText
{
	pos_x = 10;
	pos_y = 10;
	string tempString1;
	flags = visible;
	
}
function main()
{
   i = str_len(sentence);
   while(i > 0)
   {
	i -= 1;
	str_cpy(tempString2,sentence);
	str_cpy(tempString1,str_trunc(tempString2,i));
	sleep(0.5);		
   }
}

---

If you want to display word by word, may be look up "file_str_????"
in the manual.