For 10 points, name these sounds that in Germanic languages underwent umlaut and in English underwent a historical great shift, which require an open vocal tract to produce.
In Wichita and Abkhaz, these entities have only one distinctive feature distinguishing them, leading to "vertical" examples of their namesake "systems." They are the subject of the tense-lax dichotomy in some languages, and their diachronic assimilation to become similar or equal is their namesake (*) "harmony." The phenomenon of "Canadian raising" changes their height, and they can be front, back, or rounded. For 10 points, name these sounds that in Germanic languages underwent umlaut and in English underwent a historical great shift, which require an open vocal tract to produce.
In Wichita and Abkhaz, these entities have only one distinctive feature distinguishing them, leading to "vertical" examples of their namesake "systems.
vowels