Réponse :
Bonsoir,
1- John and me are dancing at this moment.
==> John and I are dancing at this moment.
( John et moi = "John and I " et non John and me )
2- Look! The children playing in the classroom.
==> Look! The children are playing in the classroom.
( Présent "be" + ing )
3- They did their bed yesterday at this time.
==> They were doing their bed yesterday at this time.
( Prétérit "be"+ing. On décrit ce qu'ils étaient en train de faire hier à cette heure )
4- Jeff is talking with her daughter right now.
==> Jeff is talking with his daughter right now.
( Jeff est un homme --> "sa fille" = his daughter )