Final answer:
The correct word to fill in the blank in the sentence is 'muy'. It means 'very' in Spanish.
Step-by-step explanation:
Estoy cansada.
The correct word to fill in the blank in the sentence is muy. The sentence translates to 'I am very tired.' The word 'muy' is an adverb in Spanish which means 'very' and it is used to intensify the adjective 'cansada' meaning 'tired'.
For example, if someone asks '¿Cómo estás?' meaning 'How are you?' and you want to convey that you are very tired, you can respond 'Estoy muy cansada.'
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