Well, basically we need to hear the "S", by hook or by crook. :D So... Words which end in an unvoiced consonant just need the "s" (books). Words which end in a voiced consonant get a "z" sound (eggs). It's much easier to say. Words which end in anything like a "s", "z" or even a "sh" or "zh" sound get the /IZ/ sound... otherwise, we simply don't hear it (gauges, bushes, masses, sentences, fezzes).

The following site has a person say aloud the words or sentence that you have typed in. Choose the accent that you like after you type in your word/sentence. http://www.oddcast.com/home/demos/tts/tts_example.php?sitepal Here are also other pronunciation sites: http://www.pronuncian.com http://www.onestopenglish.com/skills/pronunciation/phonemic-chart-and-app/interactive-phonemic-chart/