Skill Progression 30-33 months 33-36 months 36- 42 months 42 -48 months 48-54 months 54-60 months B. Possible Substitutes /f/ 75% of children: 75% of children: 75% of children: sound errors for voiceless /th/ No longer delete No longer delete No longer omit (e.g. fumb/ final consonants unstressed /s/ in an initial thumb) (e.g, ba/ball) syllables position of a cluster (e.g., 75% of children: tep/step) No longer change one sound or syllable in the word to be like another (e.g., goggie/doggie) No longer repeat syllables (e.g., baba/bottle)
Skill Progression 30-33 months 33-36 months 36- 42 months 42 -48 months 48-54 months 54-60 months B. Possible sound errors Substitutes /f/ for voiceless /th/ (e.g. fumb/ thumb) 75% of children: No longer delete final consonants (e.g, ba/ball) 75% of children: No longer delete unstressed syllables 75% of children: No longer omit /s/ in an initial position of a cluster (e.g., tep/step) 75% of children: No longer change one sound or syllable in the word to be like another (e.g., goggie/doggie) No longer repeat syllables (e.g., baba/bottle)