Task: Question Generation
Input (English): Unaspirated or tenuis consonants are occasionally marked with the modifier letter for unaspiration ⟨◌˭⟩, a superscript equal sign: ⟨t˭⟩. Usually, however, unaspirated consonants are left unmarked: ⟨t⟩.
Output (English): How are unaspirated or tenuis consonants sometimes marked for unaspiration?