Final answer:
The appropriate form of the verb être to fill in the blank in the sentence "Ils contents de nous voir." is étaient.
Step-by-step explanation:
The appropriate form of the verb être to fill in the blank in the sentence "Ils contents de nous voir." is étaient.
In this sentence, the subject "Ils" refers to a plural group, which requires the conjugated form of the verb être to also be in the plural form, which is "étaient".
For example, the complete sentence would be: "Ils étaient contents de nous voir." which translates to "They were happy to see us."
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