Release the aeroplane: 放飛機 (fong3 fei1 gei1)
Now, this is an interesting one. The story goes that when the first-ever air show was due to perform in Hong Kong many years ago, the show was cancelled on the first day because of bad weather conditions. On the second day, the weather was perfect, but the pilot was sick and unable to fly. Then, when third day came after the show had been re-scheduled, everything was ready to go... until the engine broke down!
And so, after these unfortunate three days, the whole performance was cancelled, no one got to see any planes doing tricks in the sky, and, well, that was that. From then on, the term “fong fei gei” was used to describe the act of bailing on plans, failing to show up, or breaking a promise. Basically, the worst crimes known to man!
How to use:
“Lucas had to ‘fong fei gei’ again because he’s too busy playing video games with that ‘duk naam’ Ivan!”