Why not tu instead of vous?
"Je vais penser à toi." is accepted.
just discovered that "tu" becomes "toi" after a (grave)
exactly! Why not indeed?
that's what they all say
"Je vais vous penser?"
No, penser is usually followed by an indirect object, and uses the prepostion à.
Would not ABOUT YOU be: je vais penser à ton sujet
Oops! I think that only vous works here because "vous" can be both subject and object, but "tu" becomes "toi" when it is the object.
I was marked wrong for leaving out a space between penser and à. 1 so was marked wrong. On other occasions Duo has allowed little lapses
Why not "Je vais te penser"? There is nothing after penser...