sion suffix

Core Rule

The -sion suffix forms nouns meaning action, state, or result. Its pronunciation depends on the preceding sound, typically /ʒən/ or /ʃən/, due to consonant assimilation and stress reduction.

Articulation Guide

For /ʒən/, place the tongue near the post‑alveolar ridge with voiced friction. For /ʃən/, raise the tongue blade and slightly round the lips. The stress falls on the previous syllable.

Word Analysis

decision /dɪˈsɪʒən/, expression /ɪkˈspreʃən/. Compare garage, which ends in -age and follows a different phonetic rule set.

Pitfalls

Do not confuse -sion with -tion; spelling is determined by the base word, not sound alone.