“Son las nueve menos viente de la mañana.” Literally translates to “It is 9 minus 20 of the morning.” but since literally no one talks like that it’s supposed to be “It’s 8:40 a.m.”
For #3 you could put La gente en el centro comercial nos entiende. (The people at the mall understand us.) I don't know about #4 sorry. But hopefully this helps
