neutral line的用法和样例：
例句
- Don't trap him until he goes over the central line.
等他过了中线再夹击他。 - And it's Moore to throw the ball in near the halfway line.
由穆尔在中线附近掷界外球。 - The meaning of the current account balance can be seen by comparing what is above the line with what is below it.
经常项目差额的含意可以通过对比线之上和线之下的项目看出。 - Especially, the adjacent tree graph and line graph are both included as special cases of our generalization.
特别，邻接树图和线图是我们推广的特殊情况。
