1. Conjugate stem changers in the preterite tense Essential grammar #70

2. Stem changing infinitives Stem changing infinitives are named for what they do– change in the stem. You are going to make some alteration of the stem before adding the verb endings. You will use the preterite endings you already know. The hardest part of stem changers is knowing which ones change and which ones don’t.

3. Two Rules for identifying Preterite Stem-Changers: 1. The infinitive must be a stem-changer in the present tense. 2. The infinitive must end in –ir.

4. Stem changers There are 2 different ways a stem changing infinitive can change (2 categories). -The first is o  u. -This includes present tense o  ue.

5. dormir = to sleep This is a stem changer in the preterite. First separate the stem from the infinitive ending. Dorm- is the stem. Make the stem change o  u New stem durm- Put into box– In the present tense, it looks like a boot. In the preterite tense, it looks like a sandal. Only the 3 rd and 6 th box make stem changes.

6. dormir = to sleep dormí dormí

7. dormiste dormiste

8. dormí dormí dormiste dormiste durmió durmió

9. dormí dormídormimos dormiste dormiste durmió durmió

10. dormí dormídormimos dormiste dormistedormisteis durmió durmió

11. dormí dormídormimos dormiste dormistedormisteis durmió durmió durmieron

12. Stem changers The second category is e  i. (This includes present tense changes e  ie and e  i). preferir = to prefer is a stem changer. It is the same steps as dormir. *When there is more than one vowel that could possible make the change, choose the vowel closest to the verb ending.

13. Preferir = to prefer First separate the stem from the infinitive ending. prefer- is the stem. Make the stem change e  i New stem prefir- Put into box– remember it will look like a sandal in the preterite. It will only change in the 3 rd and 6 th boxes.

14. preferir = to prefer preferí preferí

15. preferiste preferiste

16. preferí preferí preferiste preferiste prefirió prefirió

17. preferí preferípreferimos preferiste preferiste prefirió prefirió

18. preferí preferípreferimos preferiste preferistepreferisteis prefirió prefirió

19. preferí preferípreferimos preferiste preferistepreferisteis prefirió prefirió prefirieron

20. Stem changers. servir = to serve is a stem changer. It is the same steps as preferir.

21. servir = to serve First separate the stem from the infinitive ending. serv- is the stem. Make the stem change e  i New stem sirv- Put into box– remember it will look like a sandal. In the preterite, only the 3 rd and 6 th boxes show change.

22. servir = to serve serví serví

23. serviste serviste

24. serví serví serviste serviste sirvió sirvió

25. serví servíservimos serviste serviste sirvió sirvió

26. serví servíservimos serviste servisteservisteis sirvió sirvió

27. serví servíservimos serviste servisteservisteis sirvió sirvió sirvieron

28. Ellos pedir Ella repetir Nosotros sentir Usted entender Tú dormir Ella seguir Ellos pidieron Ella repitió Nosotros sentimos Usted entendió Tú dormiste Ella siguió