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.