Everyone faces times when one goal or another has to come first; deciding which goals are most important is setting priorities.（根据语句结构，划线单字的意义由is提示是指the most important goals）
A skyscraper, or building more than twenty stories high, is built on a foundation of concrete supported by piles driven into the ground.（句中or在这里表示“或者说”，提示划线单字的意义为building more than twenty stories high）
