> The essential thing is "one person = one language"
I was told this by many people but I am not sure why they say this.
My wife and I always spoke a mixture (German/French) together so of course did so also with our kid (plus English/Spanish outside the house). He had no problem, and in school or was quite orthodox in regards to which language to speak with which person. But at home or with relatives and polyglot friends he would switch back and forth. His classmates seemed to be the same.
I have seen my mother, in her 70s, switch mid sentence when arguing with her brother. Then turn and speak to my father in English.
I was told this by many people but I am not sure why they say this.
My wife and I always spoke a mixture (German/French) together so of course did so also with our kid (plus English/Spanish outside the house). He had no problem, and in school or was quite orthodox in regards to which language to speak with which person. But at home or with relatives and polyglot friends he would switch back and forth. His classmates seemed to be the same.
I have seen my mother, in her 70s, switch mid sentence when arguing with her brother. Then turn and speak to my father in English.