Step 1: On the Apple menu, click System Preferences.
Step 2: Under System, click Speech .
Step 3: On the Text to speech tab, select the Speak selected text when the key is pressed check box.
Step 4: Click Set Key, and then press the key combination that you want to use to hear text read aloud, and click OK.
Step 5: In any Office application, select some text, and then press the keyboard shortcut to hear the text read aloud.