Not subtitles. "Taking what as an example" in the title of the paper is not a subtitle, but a part of the main title. Subtitles usually appear one or two lines below the main title to further elaborate the theme or research direction of the paper. For example, the main title is "Take Tesla as an example" and the subtitle can be "Development trend and prospect of electric vehicle market". This structure can make readers understand the theme and research content of the paper more clearly. So "Take what as an example" is not a subtitle, but a part of the main title, which is used to further elaborate the theme or research object of the paper.