Rhythm, metre and tempo

Tempo uses two vocabularies. A fixed overall term -- Allegro, Andante, Adagio -- says what speed the music IS. A tempo-CHANGE term -- accelerando, rallentando, rubato -- says what happens to the speed. Asked to name a change, candidates give a fixed term (Adagio) not a change term (rallentando). Check whether the question wants the tempo or the change.

Do not read 6/8 as three even beats. Simple time divides each beat into two (2/4, 3/4, 4/4); compound time makes each beat a dotted note dividing into three (6/8, 9/8, 12/8). So 6/8 is compound duple -- two dotted-crotchet beats, each splitting into three quavers -- not simple triple. Count the beats, then hear how each one subdivides before you label the metre.

Both disturb the pulse, differently. Syncopation displaces a SINGLE accent onto a weak beat or off-beat. Hemiola re-groups the WHOLE beat pattern -- two groups of three reheard as three groups of two (or the reverse) -- a temporary metre shift without a new time signature. Calling a hemiola a rhythm trick or cross-rhythm loses the 2-against-3 detail.

A cross-rhythm or polyrhythm layers two conflicting groupings at once -- one in twos, another in threes (three-against-two). Syncopation shifts a single accent within one part. Do not call two clashing layers syncopation, or one displaced accent a cross-rhythm. Cross-rhythm is often a brief clash; polyrhythm sustains those layers across a passage.

Both are Latin/Afro-Cuban dance rhythms of different span. The habanera rhythm is a ONE-bar figure -- dotted-quaver, semiquaver, then two even quavers (long-short-medium-medium). The clave is a TWO-bar organising cell, grouped forward (3-2) or reverse (2-3), anchoring the passage. Tell them apart by span (one bar vs two) and shape, not just by hearing Latin.

Candidates often pick hemiola from multiple-choice options but cannot define it in an open answer. For the mark, state the MECHANISM, not the label: two groups of three beats reheard as three groups of two (or the reverse) within the same span, e.g. two bars of 3/4 felt as three groups of two. Without that 2-against-3 detail it will not score.

Ostinato (a persistently repeated pattern) and call and response (an alternating question-and-answer exchange) are over-used as default answers, flagged across sittings. Only name one if you can point to the actual repeating pattern or alternating exchange. Otherwise choose a term that truly fits, or accept no special device is present.