Terrell's stages are comprehension, early speech and:

1. Terrell sees learners going through three stages of acquiring speech. 2. In the comprehension stage vocabulary is bound in memory. 3. In the early speech stage learners use single words and short phrases. 4. In the speech emergence stage they join role-plays and problem solving. **Why not the others:** Correction, repetition and translation are not stages in Terrell's account of speech development. _Source: Wikipedia, "Natural approach", section "Outline" (revision 1327047924)_