I grew up bilingual and so did my first two kids. My last is trilingual. He speaks his mother's language as well as mine. All of the ceremonies he participates in are conducted in his tribe's language and he would be lost; have no understanding of the wisdom and world view of his people without knowing the language. Language is key to the transmission of culture through generations. Myriad subtleties in word usage reveal world views. One very simple example: The spanish verb esperar means not only to "wait", but to "anticipate" and to "hope".
Among native Americans, the loss of language is the precursor to the dilution of culture. I put a lot of stock in much of Whorf's views.

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You're a daisy if you do.
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