I've created a Twilio application that involves using Twilio's TwimL <Say> command to read off a list of numbers that constitute an ID that the user has previously input (e.g., 3638194746219190 or something along those lines). Since it's a long list of numbers, I have the application read back the list of numbers to confirm that the user has input them correctly. Since it's dynamic, I can't pre-record it--it has to be with <Say>, but Twilio reads it back way too quickly.
I currently have the numbers played back with spaces and commas between them to slow them down, for example: '3, 6, 3, 8, 1, 9, 4, 7, 4, 6, 2, 1, 9, 1, 9, 0', and that has helped a little bit, but it still reads the list back way too quickly.
Do you know how to force Twilio's <Say> command to slow down its text-to-speech playback even further?
You could try using periods, e.g. 1. 2. 3. 4. 5. 6. 7. 8. 9.
You can add multiple commas or periods and it'll increase the pause time. You may also consider adding longer breaks every X numbers so it has a more natural cadence to it.
3,,,6,,,3,,,8,,,,,,,1,,,9,,,4,,,7,,,,,,,4,,,6,,,2,,,1
You can add a <Pause> verb to pause execution for a number of seconds. The documentation is here: http://www.twilio.com/docs/api/twiml/pause
There's more information about generating pauses in TwiML at this question: How can I generate a half second pause in TwiML?
来源：https://stackoverflow.com/questions/13223060/slow-down-twilios-twiml-say-command-for-text-to-speech-numbers