“Go down in flames”

“Cast in stone”

Fixed and impossible to change.

“Be in over your head”

To be involved in something too difficult for you.

“Big fish in a small pond”

An important person in a small group or limited environment.

“Follow in someone’s footsteps”

To do the same thing as someone did before you.

“In full swing”

Happening with full activity and energy.

“In the driver’s seat”

In control of a situation.

“Down to earth”

Practical, realistic, and humble.

“A storm in a teacup”

A lot of anger or worry about something unimportant.