- open season (for something)
the time in the year when it is legal to hunt and kill particular animals or birds, or to catch fish, for sport （法定）渔猎开放季节 - open season for/on somebody/something
a time when criticizing a particular group of people becomes very popular, as if it is no longer important to be polite or fair （针对某些团体的）言论开放期，自由评论期