"On the other hand" is an idiomatic expression that means in contrast to what has been previously stated or understood, or in a different way than what is being said. It can also mean that two things are opposed to each other or have opposite effects.

The idiom "worm in the apple" refers to someone who ruins or spoils something by introducing a harmful or unpleasant element into it. It can also refer to someone who betrays or misleads others.

The idiom "all up" means to gather, collect, or assemble everything needed for a task or activity. It can also mean to have a total amount of something or to sum up the results of an endeavor.

The idiom "all Greek to me" means that something is so difficult or unfamiliar to me that I cannot understand it or make sense of it. It is a figurative expression used to express confusion or ignorance about a particular topic.

The idiom "come a cropper" means to fail miserably or suffer a great defeat, often involving unexpected events or circumstances that lead to the downfall of an individual, group, or organization. It can also imply taking a mistake or misstep that leads to failure.