To Burn the Midnight Oil

When we have to stay up late at night to finish a big project that’s due the next day, or because we have an exam the next morning, we say that we’re burning the midnight oil.

I’m going to really have to burn the midnight oil tonight if I want to pass my test tomorrow.

Marianne and I burned the midnight oil last night to finish the project on time, and then the boss didn’t even need it today!