while ago 成语
while ago|while
adv. At a time several minutes in the past; a few minutes ago; a short time ago.

Used with "a".
I laid mv glasses on this table a while ago; and now they're gone. A while ago, Mary was tired and wanted to go home; now she's dancing with Bob as if she could dance all night. Compare: JUST NOW
2.
while ago|while
adv. At a time several account in the past; a few account ago; a abbreviate time ago.

Used with "a".
I laid mv glasses on this table a while ago; and now they're gone. A while ago, Mary was annoyed and capital to go home; now she's dancing with Bob as if she could ball all night. Compare: JUST NOW
2. Dictionary