这条河就是在这里变窄的。

This is where the river narrows.

《牛津词典》

youdao

非洲殖民地尤其集中在大海角周围，该海角与西西里岛相对，形成了地中海主要航线上最窄的航道。

The African colonies clustered in particular around the great promontory which, with Sicily opposite, forms the narrowest channel on the main Mediterranean sea route.

youdao

And I narrow and constrict in terms of my thinking-- all I am thinking about is just that.

我的思维收窄缩紧-,一心只想着被女友甩了。

哈佛公开课 - 幸福课课程节选

In the depressed phase, our thinking is narrow; we don't think outside the box usually-- of course there's many exceptions, but as a whole.

在抑郁阶段，我们的思维收窄;,我们失去创造力-,当然有例外，但总体而言没有。

哈佛公开课 - 幸福课课程节选

And then he just takes that narrow column of light and he admits it to a prism. And what the prism does is takes a tiny, tiny difference in wavelength and refracts it through a different angle.

他只取了那个窄光柱,然后把它对准一个棱镜，棱镜所做的就是,测量出波长的细微差别,然后从不同的角度测定它的折射度。

麻省理工公开课 - 固态化学导论课程节选