If those words are commonly used in the german language, then just use the english words within the german text and mix in the german words as well. If you really want to focus you could write 2 pages to target each phrase in the correct language. But both pages should be in german of course.

Just because a foreign word is used in a language, doesn't mean you have to make the whole text in that foreign language. I doubt that the germans searching for that phrase want to specifically find an english text.

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