Hi, Vincent. Yes, to be "in a bubble" about something means to protect yourself from the harsher realities of life by only concerning yourself with the areas where you feel safe. So in a sense, you are living in isolation. You are not allowing yourself to be challenged or to grow. People can live "in a bubble" about a lot of things, including language learning.

Hi Vincent! The phrase "in a bubble" can refer to someone being isolated. The important emphasis, however, is that the person is maintaining a sheltered position. For example, someone who is living life "in a bubble" is avoiding outside influences such as new ideas or input from others. The person may even refuse to socialize with others. To learn a language "in a bubble" could be used to refer to someone who learns the form and function of the language but doesn't risk trying to use it in "real life" situations. The person remains "sheltered" from the possibility of making a mistake.

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