WILL MARK AS BRAINIEST IF CORRECT

1.) Las revistas
2.) “El libro” is the right way, you could say “Los Libro” but “Libro” is missing an s to be correct.
3.) La leche
4.) Los buzones

I'm not sure if you mean for us to translate or to answer. but i'll translate as these are questions for you to answer. 1. how long has it been since you've read a book? . 2. how long has it been since you've eaten breakfast? . 3. how long has it been since you've talked with your spanish professor?