立足于……

立足于…… means "be grounded in; base oneself on" and is used with the frame 立足于 A. Use it when you need to express this exact logical relation: take A as the foundation or starting point. Do not use it as a loose translation word; first check whether the two parts of the sentence really match the relation. Common mistakes include dropping 于 in 于-phrases, putting the key word after the object, or confusing similar patterns such as 着眼于, 基于, 依托. In formal writing, keep the clauses complete and avoid mixing two cause-result connectors unless the sentence truly needs both.