“By hook or by crook”

“Cast in stone”

Fixed and impossible to change.

“Cross your mind”

To think of something briefly.

“Cook the books”

To dishonestly change financial records.

“Hang by a thread”

To be in a very uncertain or dangerous situation.

“Cut no ice”

To have no effect or influence.

“Make it or break it”

To cause either success or failure.

“Chase rainbows”

To try to achieve something unrealistic.

“Fall by the wayside”

To fail to continue or be forgotten.