3. Watch the video:
4. Read the text
We’ll be burning the midnight oil.
That would be inadvisable.
Excuse me? If you attempt to ignite petroleum on this ship at 0000 hours, you will activate the fire-suppression system.
That was just an expression.
Expression of what? A figure of speech. I was trying to tell him that we’d be working late. “To burn the midnight oil” implies late work? That’s right.