Где это видано, где это слыхано (L)

A funny story by Viktor Dragunsky "Where has it been seen, where has it been heard." It will be about the performance of two satirists at a school concert. As you probably already guessed, satirists are Denis and Mishka. This story began with the fact that Denis Korablev was offered to sing satirical couplets at a school concert. These couplets were supposed to shame the losers and lazy people. Denis agreed and took his friend Mishka to his company for a performance. For two whole weeks the guys rehearsed and learned two verses by heart. The day of the concert soon arrived. Somehow, at once, our satirists' ardor to speak in front of the whole school diminished. But there is nothing to do. You can't let down those who prepared the performances. Friends timidly took the stage and the concert "on the topic of the day" began. This story by Dragunsky is not only funny, but also very popular. Since childhood, we have known the phrase "where it is seen, where it is heard ...". Now you know where it came from.