To keep someone in the loop: to make sure that someone is informed of what is going on. ‘I want to keep you in the loop about the possible changes to the project’.
When an idea, scheme or proposal has failed, and a new one has to be created. ‘Our suggestion for solving the problem wasn’t accepted by the client. We have to go back to the drawing board and think of a new idea’.
Bis spät in die Nacht arbeiten. To stay up late working on a project or task. I was burning the midnight oil last night so I could meet this morning’s deadline.