While:
1 (Noun) – a period of time; sometime
Examples:
A) We chatted for a while (sometime).
B) Can you lend me your bike for a while please?
C) Why can’t you wait for a while?
D) He was working here for a while.
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2 (Conjunction) – at the same time; meanwhile.
Examples:
A) He started to draw while talking.
B) She was cooking food while operating her cell phone.
C) They were fighting while I called the Police.
D) You are walking on the road while operating your cell phone.
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3 whereas (indicating a contrast or an opposite opinion)
A) Ram wants to break off, while Sita wants the relationship to continue.
B) She is buying formals while her mother is buying casuals.
C) They are cooking non-veg while their mother cooked veg.
D) You are dancing on the stage while I am singing.
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4 (Adverb) – during which.
A) The period while the dinosaurs were alive.
B) The season while mangoes were ripen.
C) It was a month while there was a vacation.