Fugue exposition — entry pitch level alternates tonic/dominant

In a standard fugal exposition, successive voice entries alternate between the SUBJECT (tonic pitch level) and the ANSWER (dominant pitch level) — canonically Subject-Answer-Subject for 3 voices, Subject-Answer-Subject-Answer (or the reverse) for 4 — but whichever pattern is chosen, it must strictly alternate; two consecutive entries at the SAME pitch level breaks the exposition's defining alternation.

A 4-voice exposition where voice 3's entry restates the SUBJECT at tonic level immediately after voice 2 also entered at tonic level, with no intervening dominant-level answer.

Standard fugue exposition pedagogy (Gedalge and the standard modern fugue-teaching tradition), not Gould/Read/Ross/Stone.

This rule needs the notated content and the rendered result together — the score says what should happen, the page says whether it did.