高考Now, several states are moving to tighten laws by adding new regulations for opting out.

现在，有几个州正在通过增加新的选择退出法规来收紧法律。

2017年高考英语北京卷 阅读理解 阅读C 原文

高考To meet this minimum goal, the agreement requires countries to tighten emissions targets every five years.

为了达到这一最低目标，该协议要求各国每五年收紧一次排放目标。

2016年高考英语上海卷 阅读理解 阅读B 原文

六级Another factor is the squeeze that conventional dairy farmers have felt as the price of grain they feed their cows has gone up, tightening their profit margins.

另一个因素是传统奶农在他们饲养奶牛的谷物价格上涨时所感受到的压力，从而收紧了他们的利润率。

2019年12月六级真题（第三套）阅读 Section B

六级They had to tighten their belts.

他们不得不勒紧裤腰带。

2012年12月阅读原文

六级You can expect that noose (束缚) to continue to tighten.

你可以期待那套套索(束缚) 继续紧缩。

2017年12月六级真题（第三套）阅读 Section B

四级As an example of the latter point, he notes growing efforts at major universities to tighten grading standards and restore failing grades.

作为后一点的一个例子，他指出，各大大学越来越努力收紧评分标准，恢复不及格的成绩。

1997年1月大学英语四级(CET-4)真题

四级For inroads (进展) to be made, say the authors in their statement, people have to be better educated about the hazards of sugar and agree that something’s got to change: Many of the interventions (干预) that have reduced alcohol and tobacco consumption can be models for addressing the sugar problem, such as imposing special sales taxes, controlling access, and tightening licensing requirements on vending machines (自动售货机) and snack-bars sell high sugar products in schools and workplaces.

对于入侵(进展) 作者在声明中说，要做到这一点，人们必须更好地了解糖的危害，并同意必须改变一些事情：

2012年12月大学英语四级真题试卷（1）