base line

柯林斯词典

1. N-COUNT The baseline of a tennis, badminton, or basketball court is one of the lines at each end of the court that mark the limits of play. (網球場、羽毛球場或籃球場的)底線[usu sing]
Martinez, when she served, usually stayed on the baseline. 馬第尼斯發球的時候，經常踩在底線上。
2. N-COUNT In baseball, the baseline is the line that a player must not cross when running between bases. (棒球場的)壘線[usu sing]
3. N-COUNT A baseline is a value or starting point on a scale with which other values can be compared. (價值的)基準[usu sing, oft N 'for' n/-ing]
You'll need such information to use as a baseline for measuring progress. 你需要利用這些信息作爲基準來衡量進展情況。