參閱Yahoo知識網時,看到 while前後詞性不同,when前後詞性相同句子等,惟不甚了解,可否舉例.謝謝?

while has the difference in meaning:-
(1)during the time that; for as long as; at the same time as:-
He fell asleep while doing his Music exercises.
While there is life, there is hope.(=as long as)
(2)Implying a contrast, whereas;
Marthar was dressed in brown, while Mary was dressed in green.
(3)Implying a concession, although:-
While she  admits that the problems are difficult, she doesn't agree that they cannot be solved.
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when as rel adv with day,time:-
Sunday is the day when I am least busy
There are times when joking is not allowed in the Chinese Congress.
It was one of those cold, wet evenings when most people stay indoors in Covid19 period.

https://www.hopenglish.com/hope-tips-whats-the-difference-between-when-and-while