1, direct subtraction: direct subtraction is the simplest calculation method. We only need to subtract the subtraction from the minuend according to the definition of subtraction, and we can get the difference. For example: 5-3=2, the advantage of direct subtraction is that it is easy to learn and suitable for the calculation of small numbers. But if the quantity is large, there may be loans, and the calculation will become very complicated.

2. Borrowing subtraction: Borrowing subtraction is the most commonly used method when we learn subtraction. In this method, the minuend and the unit of the minuend are subtracted. If the unit of the minuend is smaller than the unit of the minuend, you need to borrow from ten units.

For example: 16-8=8, we need to borrow one, and it becomes 15-8=7. The advantage of borrowing subtraction is that it has a wide range of application and can be used to calculate small and large numbers. However, there are also shortcomings, that is, we must remember the rules of borrowing and returning. Once mistakes are made, it is easy to make mistakes in calculation.

3. Complement subtraction: Complement subtraction is a relatively advanced calculation method, and it is also a method that we seldom contact when learning mathematics. In this method, we not only calculate the difference between the minuend and the minuend, but also calculate the sum of their complements.

For example: 5-3, we not only calculate the difference of 5-3, but also calculate the difference of 10-3 and 10-5, that is, 10-3 = 7,10-5 = 5,7+5 =/kl. Complement subtraction has the advantage of high calculation accuracy and does not need to consider borrowing.

However, its disadvantage is that it is necessary to remember the calculation method of complement, and it may be more complicated to borrow the complement several times in calculation. Generally speaking, these three calculation methods have their own advantages and disadvantages, and we can choose the method that suits us according to the specific situation for subtraction calculation.