El vestido means the dress in Spanish. El is 'the', and vestido is 'dress'.
1 tengo, 2 quieren, 3 tenemos, 4 quiero, 5 vi, 6 dice, 7 dio, 8 fui, 9 era, 10 hiciste, 11 hace, 12 vamos, 13 puedo, 14 puso, 15 sabe, 16 estaban, 17 estamos, 18 tiene, 19 dijo, 20 dale, 21 podemos, 22 pusiste, 23 quieres, 24 se, 25 vinieron
The answer is (usted) because you dont have a personal relationship with this person.
ustedes means you guys
vosotros means all of us
tu is used for someone whom you are close with like a family member or someone whom you have know for a while.