Level 2 — Elementary (CEFR: A2)

Unit 8 — The Three Verb Groups: Summary and Oral Reference

Lesson 8 — Drill 3: Back-Conjugation


Lesson Overview

Level: 2 — Elementary Unit: 8 — The Three Verb Groups: Summary and Oral Reference Lesson: 8 of 10 Estimated Time: 60–75 minutes

What this lesson covers:

  • The curriculum drill: hear a conjugated form, instantly produce the infinitive
  • The curriculum examples: Predicó → predicar. Creyeron → creer. Siguió → seguir.
  • Why back-conjugation is a core interpreter competency
  • The most challenging reversals: irregular preterites, stem-changed preterites, spelling-change verbs
  • Structured back-conjugation practice across all three verb groups

The Drill

From the curriculum:

Drill 3 — Back-Conjugation: Hear a conjugated form. Instantly produce the infinitive. Predicó → predicar. Creyeron → creer. Siguió → seguir.

Back-conjugation tests the interpreter’s knowledge in the hardest direction. Anyone can conjugate a known infinitive. The professional interpreter must also reverse the process: receive an unknown conjugated form and reconstruct the infinitive — the dictionary entry, the lookup word, the form on which all vocabulary knowledge is based.

The three curriculum examples illustrate the three levels of difficulty:

  • Predicó → predicar: regular -AR preterite él. Straightforward: remove , restore -ar. Easy.
  • Creyeron → creer: -ER preterite with spelling change. The y in creyeron is a surface change; the underlying verb is creer. Requires knowing the spelling-change rule.
  • Siguió → seguir: -IR preterite with e→i stem change. The surface form sig- does not look like the infinitive stem segu-. Requires knowing the -IR preterite stem-change rule.

Back-Conjugation Routes by Tense

From Present Tense

Regular: remove ending, restore infinitive ending. habla → remove -ahabl- → -AR verb → hablar come → remove -ecom- → -ER or -IR → comer or comir → confirm: comer

Irregular yo: the -go yo forms must be known from memory. tengotener hagohacer digodecir vengovenir salgosalir oigooír

Stem changes in present: restore original stem. siento → stem sient- was sent- (e→ie) → sentir pido → stem pid- was ped- (e→i) → pedir duermo → stem duerm- was dorm- (o→ue) → dormir

From Preterite Tense

Regular -AR: habló → hablar, hablaron → hablar Regular -ER: comió → comer, comieron → comer Regular -IR: vivió → vivir, vivieron → vivir

-ER spelling changes (y insertion): creyó → creer (the y appeared to separate vowels; remove it → cre- + -ercreer) leyeron → leer (same principle) construyeron → construir (same principle)

-IR stem changes in third persons (the hardest reversal): siguió → seguir (curriculum example: sig- was segu-, e→i change) sirvió → servir (stem sirv- was serv-, e→i) pidió → pedir (stem pid- was ped-, e→i) durmió → dormir (stem durm- was dorm-, o→u) murió → morir (stem mur- was mor-, o→u) sintió → sentir (stem sint- was sent-, e→i)

Irregular preterite stems (must be known from memory): tuvo → tener hizo → hacer puso → poner supo → saber quiso → querer vino → venir dijo → decir estuvo → estar fue → ir or ser (context distinguishes)

From Imperfect Tense

Regular: remove -aba/-aba/-ían, restore infinitive. predicaba → predicar creía → creer vivía → vivir

No stem changes in imperfect — simpler than preterite.

Irregulars: era → ser, iba → ir, veía → ver

From Present Perfect

Produce the infinitive from the past participle. hablado → hablar creído → creer vivido → vivir hecho → hacer visto → ver vuelto → volver puesto → poner escrito → escribir abierto → abrir dicho → decir muerto → morir

From Simple Future

Regular: the stem is the infinitive. predicaré → predicar creeremos → creer vivirán → vivir

Irregular: must know the stem-to-infinitive mapping. tendré → tener haré → hacer podré → poder sabré → saber querré → querer pondré → poner vendré → venir diré → decir saldré → salir


The Hardest Reversals: Drill Focus

These 15 forms are the ones where back-conjugation most commonly fails. Train them specifically.

Conjugated formInfinitiveChallenge
siguióseguir-IR e→i preterite 3rd person
sirvieronservir-IR e→i preterite 3rd person
durmiódormir-IR o→u preterite 3rd person
murieronmorir-IR o→u preterite 3rd person
sintiósentir-IR e→i preterite 3rd person
pidiópedir-IR e→i preterite 3rd person
creyeroncreer-ER spelling change y
construyóconstruir-IR spelling change y
hizohacerirregular preterite
dijodecirirregular preterite
vinovenirirregular preterite
fueir or sershared irregular preterite
escritoescribirirregular participle
dichodecirirregular participle
hechohacerirregular participle

Structured Back-Conjugation Practice

Round 1 — Regular Forms (Warm-Up)

A partner reads these forms. You give the infinitive immediately:

habló / comieron / vivía / predicaron / creeremos / servirá / recibió / compartíamos / decidieron / cumpliré

Answers: hablar / comer / vivir / predicar / creer / servir / recibir / compartir / decidir / cumplir

Round 2 — Irregular and Stem-Changed (Core Drill)

siguió / creyeron / durmieron / hizo / dijo / vino / fue / sirvió / sintieron / pidió / murió / construyeron / supe / puse / tendré

Answers: seguir / creer / dormir / hacer / decir / venir / ir or ser / servir / sentir / pedir / morir / construir / saber / poner / tener

Round 3 — Participles Back to Infinitives

hecho / visto / escrito / dicho / muerto / abierto / vuelto / puesto / roto / seguido / servido / vivido / predicado

Answers: hacer / ver / escribir / decir / morir / abrir / volver / poner / romper / seguir / servir / vivir / predicar

Round 4 — The Curriculum Examples Plus Extensions

From the curriculum: Predicó → predicar. Creyeron → creer. Siguió → seguir.

Extend the same drill: Hizo → hacer Sirvieron → servir Durmió → dormir Dijeron → decir Vino → venir Sintió → sentir Murió → morir Construyeron → construir Fue → ir (or ser)

Round 5 — Mixed, Fast Pace

A partner reads 20 forms in rapid succession. You give the infinitive with no pause:

habló, creyeron, siguió, hizo, dijo, vino, fue, vivían, hemos escrito, tendré, sirvieron, murió, predicaban, pudo, pondré, sintió, hablamos, han abierto, sabremos, iban

Target: 20 correct identifications, under 40 seconds total.


Why Back-Conjugation Matters for Interpretation

The interpreter’s problem is not the direction grammar textbooks teach. Grammar teaches: infinitive → conjugated form. Interpretation requires the reverse: conjugated form → meaning.

When a speaker says siguió, the interpreter must:

  1. Recognize the preterite ending (-ió)
  2. Recognize the -IR stem change (sig- was segu-)
  3. Reconstruct the infinitive seguir
  4. Access the meaning: “to follow”
  5. Produce the English: “followed”

Steps 1–4 happen in under a second in live interpretation. The only way this is possible is if the back-conjugation reflexes are trained — so the path from siguió to “followed” bypasses conscious analysis and runs on pattern recognition.


Key Takeaways

  • Back-conjugation is the hardest direction of verb knowledge, and the one interpretation actually requires
  • The three curriculum examples represent three difficulty levels: regular, spelling change, stem change
  • The 15 hard reversals must be drilled specifically — they are where comprehension breaks down
  • Target: every conjugated form from Level 2 produces its infinitive in under 1 second

Daily Practice

Five back-conjugation items daily. Choose forms from the “hardest reversals” list until each takes under 0.5 seconds. Then randomize across all tenses and groups.

Tracking method: write 5 forms on a card. Time yourself. When all 5 are under 2 seconds total, replace the card with 5 harder forms.