Final answer:
The correct pair of prepositions to fill in the blanks is 'du/de'.
Step-by-step explanation:
The correct pair of prepositions to fill in the blanks is de/du. The sentence should be 'Je suis de la Belgique et elle est du Sénégal.' The preposition 'de' is used to indicate the origin or nationality of a person, while 'du' is used to indicate the origin or nationality of a place or country.
In this case, 'Je suis de la Belgique' means 'I am from Belgium' and 'elle est du Sénégal' means 'she is from Senegal.'
Therefore, the correct answer is du/de.
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