I don't know how long this has been an option, but in System Preference, Speech, there is a preference to 'speak highlighted text' when a keyboard shortcut of your choice is pressed. I foresee minutes of hilarity to ensue, especially when I'm composing entries for public consumption.
David Wevill, a poetry professor I studied with for two semesters, always encouraged students to read aloud while composing. The internal rhythm of the line benefits with proper cadence.
Fred may help me.
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