I am a university student from China. I want to learn English by reading foreign publications and watching foreign news vedio such as BBC, Fox news, etc. And I am preparing to translate it into Chinese and subtitle the news video, then I will share it on my WeChat official accounts in order to let more people improve English. At the end of the article or video, I will give the source(including author's name) of the news or vedio and I won't request a fee to my readers, means I don't commercialize the source news and I don't profit from it. Does it still constitute infringement? If it does, how to solve it?
Yes. This is infringement.
This infringement might be excused by a "fair use" defense but it probably isn't. At a very small scale tailor to a very specific educational program, for example, for just members of a thirty person English class that they are currently taking, it might qualify as educational fair use. But I get the impression that the contemplated translation project is far more ambitious than that.
The underlying content of the events reported in the news are not protected by copyright, but the language used to report those events and any translations of that language, is protected.
The only reliable way to solve it is to get permission to do so from the holder of the copyright of the source of the new reports you are translating.