Breakdown of Me emociona que tú cantes esa canción.
tú
you (informal singular)
cantar
to sing
esa
that (feminine)
la canción
the song
Questions & Answers about Me emociona que tú cantes esa canción.
Why do we use cantes instead of cantas here?
Me emociona is an expression of emotion. When you express a feeling or emotion about an action someone else does, Spanish requires the subjunctive in the second part of the sentence. That is why the normal present tense cantas changes to the present subjunctive cantes.
Why does the sentence start with Me emociona instead of Yo emociono?
Is the word tú absolutely necessary here?
No, it is optional. Because the verb cantes is uniquely the tú form of the present subjunctive, we already know who is singing. Adding tú here just gives it a little extra emphasis, like saying "It excites me that you sing that song" (as opposed to someone else singing it).
Why is it esa canción and not eso canción?