Correct, you need to create some method for parsing your text into the format that you need spoken. Flite doesn’t have a built-in system for detecting what kind of a number it is being given (this is a good thing since it would lead to wrong assumptions). Without knowing much about your requirements, something that is fairly simple might be to just try to detect the numbers 1-9 in your text string and replace them with the equivalent word (e.g. replace “1” with “one”, etc). But if you don’t know much about the text that is coming in, or you know that a “1” could mean more than one thing if it occurs in your text, this approach might be too primitive.