972: Pane and Pain (Phoneme Inventory 1/2) Aug 7, 2017

The reason there is more than one way to spell the same sound e.g. 'pane' and 'pain' is not only because people writing English hundreds of years were inconsistent—though that did happen—but also because English used to have a greater phoneme inventory in some regards, that is to say, there were more sounds used. Of course, all languages will over time lose some sounds and gain new ones along the way, such as GH (phonetically /x/) in words like 'night' which would have been pronounced like the German CH now, which is no longer present in English. With vowels however, those that are lost weren't all dropped in the same way that /x/ was, but instead they tended to merge with other sounds. In just about all accents for English 'pain' will be pronounced /peɪn/ with the /eɪ/ sound representing a diphthong (one sound produced by two vowels), which is the same for 'pane'. The sound /e/ used to appear on its own in English though, as it would have when appearing in 'pane' a very long time ago, but eventually those two sounds were no longer distinguished. This is also the case for 'do', 'due', and 'dew', along with many other words.