It's more obvious because there are probably fewer lines there, so that you can focus on the primary line, the basic line — the bass line.

更明显的是这里也许有几条线，所以你可以将重点放在主线上，基准线，也就是低音线。

youdao

This equipment is easy to be fixed for its small volume. It doesn't change the primary line and has no impacts on the insulation of transmission line.

该装置体积小，安装简便，不对原一次线路进行改动，不对线路绝缘造成威胁，解决了配电网分支线路无功参数不易测量的难题。

youdao

So the line is the primary side and the secondary side.

所以，这条线是主要的一面,还有第二面。

youdao

It's more obvious because there are probably fewer lines there, so that you can focus on the primary line, the basic line--the bass line.

更明显的是这里也许有几条线，所以你可以将重点放在主线上，基准线，也就是低音线。

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