rack one`s brains
to try hard to think of something or remember something
I have been racking my brains all day trying to remember the man's name.
Chinese New Year
Red packets almost always contain money, usually varying from a couple of dollars to several hundred. Per custom, the amount of money in the red packets should be of even numbers, as odd numbers are associated with cash given during funerals. The number 8 is considered lucky (for its homophone for wealth), and $8 is commonly found in the red envelopes in the US. The number six is also very lucky as it sounds like smooth, in the sense of having a smooth year. The number four is the worst because its homophone is death Sometimes chocolate coins are found in the red packets.Odd and even numbers are determined by the first digit, rather than the last. Thirty and fifty, for example, are odd numbers, and are thus appropriate as funeral cash gifts. However, it is common and quite acceptable to have cash gifts in a red packet using a single bank note