¡Hello!
In this exercise, someone says a sentence expressing something and another person need to reply in Subjunctive mood. You have to use the subjunctive when expressing doubts, desires, unknown things, abstract things, negation and emotions. It's important to say that Subjunctive sentences often use parts linked by a relative pronoun, wich are: que, quien, como.
Question 1
Original Sentence: Éste ha sido tu mejor año.
Subjunctive Mood: No estoy segura que éste haya sido mi mejor año.
In this case, the sentence expresses doubts
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Question 2
Original Sentence: El ejercicio le ha aliviado el estrés.
Subjunctive Mood: Dudo que el ejercicio le haya aliviado el estrés.
In this case, the sentence expresses doubts
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Question 3
Original Sentence: Rafael y tú han sufrido muchas presiones.
Subjunctive Mood: Niego que Rafael y yo hayamos sufrido muchas presiones.
In this case, the sentence expresses negation
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