I think that every learner of a foreign language has to decide at a certain point whether they are going imitate native speakers, so as to be mistaken for something they are not, or to retain something of their own character and nationality.
If you are reading something about food, you might see a complete phrase or sentence in a foreign language appear without explanation. I am thinking particularly of Italian. It used to be common practice at one time for menus to be printed in French.
To answer this question, I would like you to include some good examples, possible in speech as well as in written English.