New English

Palatalisation –as a result of reduction of unstressed vowels several consonants merged into one:

ME Sounds NE Sounds ME NE
[sj] à [∫] commissioun [komi’sjon] commission [kə’mi∫ən]
[zj] à [ζ] pleasure [plə’zjurə] pleasure [‘pleζə]
[tj] à [t∫] nature[na’tjurə] nature[‘neit∫ə]
[dj] à [dζ] procedure [,prosə’djurə] procedure [prə’sidζə]

There were some exceptions though, e.g. mature, duty, due, suit, statue, tune, etc.