For example, the knowledge points in Unit 4 are:

1. A whole ten, a whole hundred or a few hundred dozen divided by one digit: divide the number before the whole ten, a whole hundred or a few hundred dozen by one digit first, and then calculate the quotient.

2. Dictation of two digits divided by one digit: Dictation of two digits divided by one digit, first dividing the two digits into integer ten digits and one digit, then dividing by one digit (divisor) respectively, and finally adding the quotients divided twice.

3. Written calculation of dividing two digits by one digit: (1) Divide two digits by one digit, divide the number on the tenth digit first, and write the quotient on the tenth digit; (2) Divide the number on the unit and write the quotient.