The idiom "boil the ocean" means to try to do something that is beyond one's capabilities or to take on more than one can handle. It often implies trying to do something quickly or efficiently, but ultimately failing.

The idiom "ups and downs" refers to the fluctuation of something, or the rise and fall of events. It can describe a person's mood, business finances, or any situation that has its highs and lows.

The idiom "in broad daylight" refers to a situation where something is happening openly, publicly, and without any concealment or secrecy. It can also indicate that an action is being taken with no fear of retaliation or harm.

The idiom "come again" is primarily used to request that someone repeat a statement or utterance. It can be used to clarify misunderstandings or to seek confirmation. The phrase may also be used sarcastically to express disbelief or surprise at what someone has just said.

The idiom "more than meets the eye" is used to describe something that appears to be ordinary or simple but has hidden depths or complexities. It suggests that there is more to a person, situation, or thing than what is immediately apparent.