When the Label Is Right but the Reasoning Is Wrong: Secondary Dominant in G Major
Mr. Alvarez teaches Music Theory I to 24 high school students, six of whom study privately. Today the class is analyzing an eight-bar progression he has written on the board in G major: G – C – G – E7 – Am – D7 – G, with the E7 spelled E–G♯–B–D. He asks each group to supply Roman numerals. Group A writes V7/vi and calls the E7 a secondary dominant. Group B insists the chord is 'borrowed from G minor,' because the class recently learned that chromatic tones often come from the parallel minor, and they point out that G♯ is not in the G major scale. A guitarist in Group A adds that the chord 'just sounds bluesy.' With 20 minutes left, Mr. Alvarez must decide whether to settle the labeling dispute, use the disagreement to teach harmonic function, or move on to the next objective on his pacing guide, which is cadence identification.
1. Evaluate the two groups' labels and reasoning. What does each group understand, and what does each misunderstand? Then state what Mr. Alvarez should do with the remaining 20 minutes and defend that choice.
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Group A is correct in label, incomplete in reasoning. E7 is V7/vi: it is the dominant seventh of A minor, the vi chord, and it contains the leading tone G♯ that pulls to A. But if the guitarist's justification is 'it sounds bluesy,' the group may be identifying the chord by color rather than by resolution. A secondary dominant is defined by where it goes and by the tritone inside it (G♯–D), not by its sound alone.
Group B is wrong, and instructively wrong. G minor contains B♭ and E♭, not G♯. If mode mixture were operating here, the borrowed pitch from G minor would be B♭ (producing E minor seventh-flat-five or an E♭ chord), not G♯. Group B has a real concept - chromaticism often enters through mixture - but has misapplied it, because they are testing scale membership instead of function.
Use the 20 minutes on function, not on the label. Two reasons: the pacing-guide objective, cadence identification, depends entirely on whether students can hear a dominant resolving, and this dispute is a symptom of a missing functional understanding rather than a vocabulary gap. Spending the full 20 minutes adjudicating Roman numerals rewards the students who already know the rule and leaves Group B's misconception untouched.
Sequence: three minutes to resolve the label at the board (spell E7, circle the tritone, show the resolution to Am); twelve minutes of singing/playing so the resolution is audible; five minutes returning to cadence identification with the new hearing in place. Close by asking Group B to name the pitch that would have come from G minor - the conceptual repair matters more than the correction.
2. Design a 10-minute aural/performance activity that lets students hear the difference between a secondary dominant and a borrowed chord before they label either one. Specify what students sing or play and what the teacher should listen for.
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Objective: students feel the pull of a chromatically raised tone toward its resolution, then compare it with a chord that supplies color but not pull.
Minute 0–2: establish the key. Teacher holds a G drone on piano or a barred instrument. Class sings the G major tonic triad, then the scale, then settles on la (E) to hear where the home key sits. No labels yet.
Minute 2–5: add the raised tone. Teacher plays E7 while the class sustains la. Ask who can find the note that 'does not belong.' Once G♯ is found, have the class sing G♯ against the drone, then resolve G♯ up to A while the teacher plays E7 to Am. Do this four times, alternating who sings the G♯ line and who sings the E pedal.
Minute 5–8: comparison. Teacher plays G – Em7 – Am, then G – E7 – Am. Students raise a hand when they hear the chord that 'leans.' Discuss: the Em7 shares three of four pitches with E7 and still sounds like a color change; the G♯ is what creates the lean.
Minute 8–10: transfer. Half the class sings a bass line G–C–G–E–A–D–G while the other half sings chord tones; swap. Then students write the numeral for the chord they just heard resolve.
Listen for: accurate intonation of G♯ as a rising tendency tone (not a flat, static pitch); ability to hold an independent part while the harmony moves; and verbal descriptions of tension and destination rather than 'sad' or 'happy.' Students who label correctly but describe the chord as merely 'major' have not yet heard function.
3. Write one constructed-response assessment item that separates students who can generalize the concept from students who have memorized that E7 is V7/vi.
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Item (one class period, no notes):
'Consider this progression in F major: F – B♭ – F – D7 – Gm – C7 – F.
(a) Give the Roman numeral for the D7 and identify the chord it resolves to. (b) Name the chromatically altered pitch in the D7, state which scale degree it is in the key of F, and explain in one sentence where that pitch comes from. (c) Now suppose the chord after D7 were G major instead of G minor. Would your Roman numeral change? Explain. (d) A classmate says the D7 is borrowed from F minor. In two sentences, explain why that claim is or is not accurate.'
Why this separates the two groups of students. Part (a) alone is recall in a new key - some students will transpose the G-major answer without understanding it. Part (b) requires them to locate the chromatic pitch by function, not by memorized spelling. Part (c) is the discriminator: the same sounding chord carries a different Roman numeral depending on its resolution, which is only answerable if the student understands secondary dominant function. A student who memorized 'E7 in G is V7/vi' will likely answer (c) incorrectly by treating the numeral as a property of the chord rather than of its destination. Part (d) forces them to use the mixture concept Group B raised, which surfaces whether they can distinguish 'chromatic' from 'borrowed.'
Scoring: 4 points, one per part; part (c) weighted double. A student scoring 5/5 has generalized. A student scoring 2/5 has vocabulary without function and needs the singing activity again, not more worksheets.