second language

音标发音

This is an especially good translation for people who speak English as a second language.
对英语作为第二语言的人讲，这是一个尤其好的译本。
Well over half our audiences have English as a second language, and on some services the proportion is as high as 80%.
我们有一大半受众把英语作为第二语言，而对某些市场而言，这个比例高达80%。
English is the city’s second language, closely followed by Russian and Turkish.
英语是这座城市的第二语言，紧接着是俄语和土耳其语。

Through the implant process,called Intra-cranial Electrophysiology,or ICE, the researchers have found that Broca's area processes three different language functions in succession within a quarter of a second.
It turns out that if you start learning a language, a second language is where most of the work's been done, within the first few years of life you're fine.
如果你在出生的头几年里开始学习一门语言,非常努力地学习了第二门语言,那么你一切正常
耶鲁公开课 - 心理学导论课程节选
What do you think is the most important thing to teach students who learn English as a second language?
你觉得要教那些以英语为第二语言的学生，最重要的是什么？
教英语 - SpeakingMax英语口语达人

The group found that many students received minimal or no help in developing their second language.
NPR: Instruction Of Students Learning English Bleak

a language that a person can speak that is not the first language they learned naturally as a child

Someone's second language is a language which is not their native language but which they use at work or at school.

第二语言
English is neither our mother tongue nor second language.
英语不是我们的母语,也不是第二语言。
心理学
第二语言