“Youth” has several meanings but often with an old-fashioned, condescending, daddy-knows-best feel to it.
“Performance” is the noun that comes from “to perform”. But it’s not the right word to use for carrying out tasks or doing work: the overtones are too confusing.
Your everyday, common-or-garden patch of countryside with trees is a wood or woodland. Forests are bigger, darker and nastier; jungles are definitely more exotic.
Dutch is rich in synonyms (often pairs with Germanic and Latinate roots). The nuances of usage aren’t quite the same – and it’s an issue in English too.
To ‘seek’ is another of those words that are very similar to a much more everyday Dutch equivalent. It therefore gets heavily overused in Dunglish.
When two different prepositions are needed in a list of actions, it can read better if you repeat the noun (or use “it” or “them” as a placeholder).
Don’t assume that Latin in Dutch medical texts will be the same in English: this is often not the case. Abbreviations in particular can be incomprehensible to English speakers, even doctors
The plural of person is ‘people’, except in legalese and occasional old-fashioned texts.
Would you want to be operated on by a surgeon whose skills are adequate? Or would you rather have one who’s good?
It’s not a word. (Well, just about, deep in the dark depths of the dictionary. But that doesn’t make it correct.)