In a way that does not match how things really are. It is the adverb of unrealistic, and it almost always sits in front of an adjective describing an amount or a level: unrealistically high, unrealistically low, unrealistically cheap, unrealistically fast, unrealistically thin. "The price was unrealistically low." "The deadline is unrealistically short." When you use it, you are not just measuring something — you are judging it. You are saying: this number, this hope, this picture of the world could not actually happen, and someone has failed to see that. So there is usually a quiet criticism inside it. If you say a company set unrealistically high targets, you are saying the managers were foolish or dishonest, not merely optimistic. It also gets used a lot when talking about pictures and media — models in advertisements are described as unrealistically thin, films as showing unrealistically perfect lives. Here it carries a small note of complaint on behalf of ordinary people. It can attach to a verb too ("he plans unrealistically"), but that sounds stiff; the natural home of this word is right before an adjective. It is a long word and a slightly formal one — in everyday speech people are more likely to say "way too high" or "that's never going to happen."

不切實際地、不實際地（多用在「高得離譜」「低得不合理」這種評價上）