Final answer:
The conjugation of pagar in the subjunctive (el/ella/ud) form is pague.
Step-by-step explanation:
The subjunctive form of pagar in the third person singular (el/ella/ud) would be pague. To conjugate a verb in the subjunctive, you typically take the yo form of the present tense, remove the -o ending, and add the appropriate subjunctive ending. In this case, the -o ending is changed to -ue to maintain the /ɡ/ sound in the stem.
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