Word's ReadAloud incorrectly speaks double (f″(x)), triple (f‴(x)), and quadruple (f⁗(x)) prime notation in mathematical expressions

[brichwin]

Bug Description

When using the ReadAloud feature in Microsoft Word 365, it incorrectly speaks mathematical expressions containing double prime (″), triple prime (‴), and quadruple prime (⁗) notation.

Here is a video demonstrating the issue: Video: ReadAloud Not Speaking Double, Triple, and Quadruple Prime Unicode Characters and Misreading Expressions Containing Them (4.5 minutes)

Here is the file used in the video:
Examples of Prime Notation.docx

Current Behavior

• Single prime (′) is read aloud correctly: "f\prime(x)" is spoken as "f prime of x"
• Double prime (″) is incorrectly read aloud: "f\pprime(x)" is spoken as "f to the open paren x close paren"
• Triple prime (‴) is incorrectly read aloud: "f\ppprime(x)" is spoken as "f to the open paren x close paren"
• Quadruple prime (⁗) is incorrectly read aloud: "f\pppprime(x)" is spoken as "f to the open paren x close paren"

Expected Behavior

• "f\pprime(x)" (double prime) should be read as: "f double prime of x"
• "f\ppprime(x)" (triple prime) should be read as: "f triple prime of x"
• "f\pppprime(x)" (quadruple prime) should be read as: "f quadruple prime of x"

Steps to Reproduce

1. Open Microsoft Word 365
2. Enter the following mathematical expressions using Equation Editor using the UnicodeMath format:
   • f(x) = x^5
   • f\prime(x) = 5x^4
   • f\pprime(x) = 20x^3
   • f\ppprime(x) = 60x^2
   • f\pppprime(x) = 120x
3. Use Review tab to activate ReadAloud's default settings (Microsoft David)
4. Listen to how each expression is read

Environment

• Microsoft Windows 11 (fresh build)
  • Windows 11 Home Version 10.0.22631 Build 22631
  • Microsoft Word 365 Version 2410 (Build 18129.20158 Click-to-Run) Current Channel
  • Default ReadAloud settings
    • Microsoft David voice
    • Default reading speed
• macOS Sequoia
  • macOS 15.1.1 MacBook Pro Apple M3 Pro
  • Microsoft Word for Mac Version 16.92 (24120731), Microsoft 365 Subscription
  • Default ReadAloud settings
    • Reed (English (US))
    • Default reading speed

Impact

In mathematical and scientific contexts, derivative notation is common. The incorrect reading can lead to misunderstanding of mathematical concepts and formulas.

Additional Notes

• The issue only affects multiple prime notation (double, triple, quadruple) using the Unicode characters for them
• Single prime notation is read correctly
• The behavior is consistent across Windows 11 and macOS tests