I believe that in the blank should go "sabemos"
I hope I'm correct.
Answer:
Both. Depends on the situation.
Explanation:
"Ti" would be you as the object. Mainly after prepositions, "ti" is always used (por ti, para ti, a ti, etc.). "Te" is also for a direct/indirect object and is used when there's no preposition.
English translation:
"The subjunctive is used for expressing _____".
In Spanish, subjunctives are used for expressing emotion. The word that best fits 'emotion' from the answer choices listed is deseos (desire), as it states an emotion.