To have had one's day under the sun is to have enjoyed a brief period of prominence.

During the meeting, the CEO's unexpected announcement cut the ground from under someone's feet, leaving him with no time to adjust his pitch.

As my grandfather used to say, one can't carry two watermelons under one arm, so choose your commitments carefully.

She underacted the role of the grieving mother, choosing subtle gestures over overt displays of sorrow.

By underacting the role, he made the antagonist seem less threatening.

She underacts in emotional scenes to avoid melodrama.

Her underactive thyroid made her feel constantly tired and sluggish.

She kept underachieving despite extra tutoring and support.

Although she underachieved in the final exam, her hard work improved her overall understanding.

Despite his obvious talent, he underachieves in high-stakes exams.