We all know that personal tax is based on the cash basis or the accrual basis, which means that even if the money is earned but not yet in the account, it is not counted as the income of the year; the same is true for expenses. If they are not spent, they cannot be counted as the expenses of the year and used to offset the income of the year. Although everyone understands the principle, it is still easy to make mistakes in the actual operation. Among many investments, stock investment is very common. If you have a lot of stock income, but don’t want to pay more taxes, then the general principle is to sell some losing stocks before the end of the year, and the stocks that cannot be turned around in a short period of time, so that the losses from the sales can be offset against the profits, thereby achieving the purpose of paying less taxes. However, under this general principle, there are some restrictions and rules that you need to know to avoid unnecessary losses and troubles.