"A wolf in sheep's clothing" is a warning. It warns us to not trust someone just because they seem nice on the outside.

The expression "that ship has sailed" means your chance to do something has passed.

If someone says you look like a "deer in the headlights" it means you look frozen with surprise, shock, or maybe even fear.

A "bucket list" is a list of things you want to do before you die.

To "keep your eye on the ball" means to keep your attention on something important to you -- usually to reach a goal.

A moving target is a goal that keeps changing.

Breaking even means the point at which costs and earnings are equal.

To "push the envelope" means to go beyond the limits of what is usual.

"The last straw" is that last little difficulty - in a long series of difficulties - that makes you quit.

Baggage is all those issues that hold you back and keep you from moving forward in life.

A "fly on the wall" is someone who wants to listen to other people's conversations, without being noticed.

"At the drop of a hat" means to act quickly, without delay or much planning.

"Cool as a cucumber" describes someone who is laid-back or who performs really well when the pressure is on.

To "put someone on the spot" means to put them in a tough or uncomfortable situation.

To fall "down the rabbit hole" is used to describe an unusual, unfamiliar place.