while · conjunction /wɑɪl/Full view
while (DURING)
A2 during the time that, or at the same time as
Dictionary examples:

I read it while you were drying your hair.

While I was in Italy, I went to see Alessandro.

I thought I heard him come in while we were having dinner.

"I'm going to the post office." "While you're there, can you get me some stamps?"

Learner example:

My mother gave it to me yesterday evening while I was playing [a] comp[u]ter game. (Key English Test; A2; Chinese)

while (COMPARING)
B1 used to compare two different facts or situations
Dictionary examples:

He earns seventy thousand dollars a year while I earn only forty!

Tom is very confident while Katy is shy and quiet.

Learner example:

In Italy, weddings [are] very traditional! The girls [wear] a long, white dress, while the boys, normally, [wear] dark [clothes]. (Preliminary English Test; B1; Italian)

while (ALTHOUGH)
B2 despite the fact that; although
Dictionary examples:

While I accept that he's not perfect in many respects, I do actually like the man.

While I fully understand your point of view, I also have some sympathy for Michael's.

Learner example:

While it is true that everyone should have a computer at home because it is useful, on the other hand hardly anybody [can] afford [one]. (First Certificate in English; B2; Italian)

while · noun /wɑɪl/
a while
B1 a length of time
Dictionary examples:

I only stayed for a short while.

You were there a while, weren't you?

"When did that happen?" "Oh, it was a while ago".

After a while, Roberto came back inside.

I haven't seen him for a while.

I'll be fine in a while.

Learner example:

After a while, a girl invited me to play darts with her and her friends. (Preliminary English Test; B1; Italian)

quite a while
B1 a long time
Dictionary examples:

I hadn’t seen Rebecca in quite a while.

It took quite a while to clean out the garage.

Learner example:

But although I have what you could call "simple" tastes, it takes me quite a while to decide what to buy. (Preliminary English Test; B1; Spanish)

(every) once in a while
B2 sometimes but not often
Dictionary example:

We do go to the beach once in a while.

Learner example:

She did not say very much except for "oh" and "yes, yes" every once in a while. (First Certificate in English; B2; Dutch)

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