English for Today by Ganiu Abisoye Bamgbose (Dr GAB)
Do you burn the midnight candle?
He slept for three hours this morning after burning ~the midnight candle~ (nonstandard).
He slept for three hours this morning after *burning the midnight oil* (standard).
If someone is burning the midnight oil, they are staying up very late in order to study or do some other work.
However, one can burn the candle from both ends. This idiom means to work or do other things from early in the morning until late at night and so get very little rest:
He is sick now because he had to *burn the candle at both ends* for days.
Dr GAB
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