The phrase “I’ve been on my best behavior” is typically used to indicate that someone has been acting in a particularly well-behaved or polite manner, often in order to make a good impression or avoid getting into trouble.
There are many reasons why someone might choose to be on their best behavior. For example, they may be in a situation where they need to make a good impression, such as a job interview or a first date. They may also be trying to avoid getting into trouble, such as when they are around someone who is known to be strict or authoritarian.
