1, horizontal row is called row, vertical row is called column. Determine which column is usually counted from left to right and which row is usually counted from front to back.

2. Using two numbers to indicate a position in turn is a number pair, and two data are needed to determine the position of an object.

3. When the position is represented by a number pair, which column is represented first, and then which row is represented. Don't confuse columns with rows.

4. When writing a number pair, enclose the number of columns and rows in brackets and separate them by writing a comma between them. Write: (column, row).

5. Logarithm of reading: (2,3) You can read (2,3) directly, or you can read it as a number pair (2,3).

6. A set of number pairs can only represent one position.

7. Number pairs representing the positions of objects in the same column have the same first number; A pair of numbers representing the position of an object in the same row, whose second number is the same.