Answer:
1. han llegado
2. han traido
3. he visto
4. han mejorado
Explanation:
I am Mexican-American and know what I'm talking about. You use the spanish forms of "to do" and the PAST participle of the word, in the case of number 1, "han llegado" means "have arrived." You repeat this process until you finish.
1-3 i cannot explain, it is difficult to explain for me
4, so number 4 should be, yo bailaré
5, Ellos estan bailando
6, yo hablare, because yo hablo is signifying you speak and yo hablar is not the proper way to say it
Its letter A (estes) its talking abt present time