“Keep your fingers crossed”

“Fat chance”

Very little or no chance.

“Earn your stripes”

To prove your ability through hard work.

“Fight fire with fire”

To use the same methods as your opponent.

“Keep at bay”

To prevent something from coming close or becoming a problem.

“Fit as a fiddle”

Very healthy and strong.

“Food for thought”

Something worth thinking about.

“Keep tabs on”

To watch or monitor carefully.

“For a song”

For a very low price.