it is sunday .a little duck comes to a city .he doesn't like to be at home all the time .now he is very happy

it is sunday .a little duck comes to a city .he doesn't like to be at home all the time .now he is very happy
suddenly ,a car is coming .it is running too fast .the little duck is afraid ,but he is very smart .he jumps over from the front of the car to the back of the car
now the duck is sitting in the street .there is nothing wrong wuth him .but he is very angry .he thinks ,"i cannot let go .i know your car number is 9186"
the little duck stands up and goes to the police station .he tells the police the car's number .very soon ,the police find the car .its number is 9186 .later ,the little duck smiles and says " oh ,i made a mistake ." i may get the wrong guy
1.What mistake did the duck make?
2.给本文拟一个合适的标题