The idiom "once bitten, twice shy" means that someone who has had a negative experience is more likely to be cautious or hesitant in the future.

The idiom "how come" is used to express surprise or disbelief about a situation, person, or thing. It can also be used to ask for an explanation or reason why something happened. The literal meaning of the phrase is "for what purpose" or "why.

The idiom "wash dirty linen in public" refers to exposing a problem or issue that is best left private or hidden. It suggests that airing dirty laundry, or bringing up unpleasant topics or details, can harm one's reputation or image.

The idiom "make a mountain out of a molehill" means to exaggerate or make a big fuss over something that is insignificant or unimportant. It is often used when someone is overreacting to a small issue.

The idiom "tasted blood" means to feel a sense of satisfaction or triumph after achieving something, often at the expense of someone else. It implies a desire for revenge or retribution.