First, you can mix single and double quotation marks when creating a string, as long as the string USES the same type of quotation mark at the beginning and end.

第一，在创建字符串时，您可以混合使用单引号和双引号，只要字符串在开始位置和结束位置使用同一类型的引号。

youdao

This paper introduces the principle of double barrel drum mix plant and the application in producing the asphalt mixture, aiming at the rounding town project of Foshan.

阐述了双滚筒连续式拌和楼的工作原理，并以佛山一环城际快速路为工程依托，介绍其在沥青混合料生产中的应用。

youdao

The double layer of liquid crystal system are mix structure of non linear, non ideal and non equilibrium.

膜系统的液晶态双层相是非线性非理想非平衡态的混合结构。

youdao

The meeting was part of a new initiative that aims to achieve universal access to modern sources of energy, double the share of renewable energy in the global energy mix and double the rate of improvement in energy efficiency, all by 2030.

FORBES: Sustainable Energy for All: How to Fight Poverty and Climate Change

It turns out that this kind of mix-'em-up creativity is a double-edged sword for a man of Powell's clout in the industry.

CNN: Helping 'Bourne' rise to the occasion

Then, this week, the King Institute of Preventive Medicine, a flagship government hospital in the Tamil Nadu capital of Chennai, announced its intention to do a double-blind study to see how effective the neem-papaya mix is in battling dengue.

FORBES: Is Ancient 'Mocktail' The Answer To Dengue Fever?