Decoding exercises: "ss"

In English, both in Received Pronunciation and in General American, "ss" normally corresponds to the IPA phonetic symbol /s/ in words like "class" or "possible". In a few words "ss" is pronounced /z/, as in "dessert" or "scissors". In combination with a vowel "ss" is often pronounced /ʃ/ as in "issue" or "discussion".

As /s/

 * In final position: access - across - address - business - class - cross - discuss - dress - express - guess - less - loss - miss - pass - press - process - success
 * In middle position: asset - assessment - associate - assume - essential - impossible - lesson - message - necessary - passenger - possible - professor - successful

As /z/
This list is fairly complete (obvious derivatives are not included).
 * In middle position: Aussie - brassiere - dessert - dissolve - hussar (a soldier) - Missouri - possess - possession - scissors - Tassie (from Tasmania, also spelled Tazzie)

As /ʃ/

 * "ssi": commission - depression - discussion - expression - impression - mission - passion - possession - professional - Russia - session
 * "ssu": assure - issue - pressure - tissue

Commonly confused words

 * dessert (sweet food) /dɪˈzɜːrt/ - desert (abandon) /dɪˈzɜːrt/ - desert (dry place) /ˈdzərt/

Two different syllables
/s.s/
 * disservice, dyssomnia, misspeak, misspell

/z.s/ or /s.s/
 * transsexual

Anticipated pronunciation difficulties depending on L1
Preconceived ideas and other interferences from L1 obviously interfere in many cases with how students perceive - and pronounce - sounds/words in English. The following section aims to point out some of the most typical difficulties teachers and students may encounter regarding pronunciation.

Spanish
Beginner Spanish speakers may pronounce "ssi" as /sj/. For example "discussion" can be pronounced, which is similar to Spanish [diskuˈsjon].