.It is no use ______ after you know your failure.

Evidence obtained from observation and experiment is often used to _____ a scientific theory.

— Did Alice enjoy the concert held in Grand Theater yesterday? — Yes, she did. She _____ such an excellent concert for a long time.

Whoever _____ a new idea of how to work out the puzzle will be given a prize.

 Rescuers had to _____ the search because of worsening weather conditions.