Assertion: english diphthong | /r/CapableOf | merge into monophthong
Facets:
Source sentences:
text: Although the Old English diphthongs merged into monophthongs, Middle English began to develop a new set of diphthongs, in which the second element was a high [i] or [u]. Many of these came about through vocalization of the palatal approximant /j/ or the labio-velar approximant /w/ (which was sometimes from an earlier voiced velar fricative [ɣ], an allophone of /ɡ/), when they followed a vowel.