Hi Ilka,
you’re right. Languages have always changed. We can hardly understand texts in Old High German, and even words used in the popular songs of the Roaring Twenties seem kind of strange to us.
All languages are influenced by others, by people who come together and try to find a way to communicate.
Sometimes old languages become popular again, as it is in Catalonia, where many people speak Catalan instead of Castilian Spanish.
Concerning the German language we shouldn’t worry. People in China, for instant, are very interested in learning German, our difficult, but very fine language.
And when I read the texts of the many young poets, I know that the German speaking people love their language anyway.
Greetings from Berlin,
Jenny