what is "sb/sth"? This isn't a word. Perhaps you mean "To take someone for granted." "She just took him for granted." This means the person is not appreciated. Look, are you sitting in a chair at your computer? When you sat down did you even think about it? Were you grateful that you have a chair to sit on? If you didn't have a chair, you'd have to sit on the floor. Isn't that worth being appreciative of the chair? If you didn't think about it, you took your chair for granted. You just assumed it would be there and would support you. It's fine to take furniture for granted. If it breaks you can get another one. But to take a person for granted is not very nice. No one likes it. The war took on a different meaning. Let's say you are on a train and some kids are being very obnoxious and annoying. They are loud and screaming and the father just ignores them. You try giving him dirty looks, but he doesn't get it. Finally the father sees you and says, "I'm sorry they just lost their mother, and they are freaking out. She just died this morning. I'm not really sure what to do." Perhaps now you want to help him and his kids, or at least your perspective has changed. The situation has now taken on a completely different meaning. The situation didn't change, but your perspective of it has.