Saying it to the wrong year. "New year" in Chinese, xinnian,
can mean January 1 as well as the lunar one. On a New Year card that arrives in the
first week of January, xinnian kuaile is read as the Western holiday. If you
mean the lunar festival and the date is ambiguous, say chunjie kuaile, "happy
Spring Festival," or guonian hao, which only ever means the lunar one.
Wishing money on someone who wanted health. The older the listener,
the less facai belongs at the front of the sentence. Lead with health, add
long life, and if you want the prosperity wish put it last.
The child's rhyme. Hongbao nalai is for children. Adults who
say it to a boss or an in-law have asked for money out loud, and the room will decide
whether it was a joke.
Congratulating the bereaved. A household that has lost someone in the
past year traditionally neither pays nor receives New Year calls, hangs no red, and does
not want gongxi. A quiet wish for health, and an envelope only if you are
family, is the register. The sixth-century Jingchu Suishiji already has the
family greeting each other in order of age on the first morning; what it does not have
is anyone greeting a house in mourning, and that silence is the custom.
Saying the unlucky thing. The season runs on sound-alikes, so anything
that sounds like death, loss or breaking is talked around: a dropped bowl is answered with
"peace year after year," because "shattered" sounds like "year," a bad hand of cards is not mentioned, and the number four stays out of
greetings and envelopes alike. Conversely the lucky sound-alikes are the whole game,
which is why fish is on every table (yu, "surplus") and a Rooster year is a
great one for luck (ji, "chicken," sounds like ji, "auspicious").