TextEdit can speak the text in a document. It can speak all the text or only selected text.
To speak all the text in the document, open the document, and then choose Edit > Speech > Start Speaking.
To speak only a portion of the text in a document, select the text, and then choose Edit > Speech > Start Speaking.
To make the speaking stop, choose Edit > Speech > Stop Speaking.
To change the computer’s speaking voice, open the Speech pane of System Preferences and click “Text to Speech.” Next, choose a voice from the System Voice pop-up menu.