除了一个男孩，所有的人都开始把数字写在练习本上。

All of them begin to write the Numbers down except one boy.

youdao

在此练习中您要对一个给定的数字作因数分解。

In this exercise you have to factorize a given number.

youdao

然后他在练习本上写下一个数字并举起手。

Then he write a number in his exercise-book and put up his hand.

youdao

然后他在练习本上写下一个数字并举起手。

Then he write a number in his exercise-book and put up his hand.

youdao