2. Monthly interest: 20,000× 0.03 = 600 yuan.

3. Monthly repayment: 555.56+600 =1155.56 (RMB).

That is, 1 155.56 yuan should be paid back every month.

Legal basis: Civil Code of People's Republic of China (PRC).

Article 574 If the loan term is less than one year, it shall be paid off at the time of repayment; If the loan term is more than one year, it shall be paid at the end of each year; If the remaining term is less than one year, it shall be paid together with the repayment.

Article 675 The borrower shall repay the loan within the agreed time limit. If the term of the loan is not agreed or clearly agreed, and cannot be determined according to the provisions of Article 510 of this Law, the borrower may return it at any time; The lender may urge the borrower to return it within a reasonable period of time.

Article 680 usury is prohibited and the loan interest rate shall not violate the relevant provisions of the state.

The Supreme People's Court's Opinions on the Trial of Lending Cases by People's Courts Article 6 The interest rate of private lending may be appropriately higher than that of banks, but it shall not exceed four times the interest rate of similar loans of banks (including the principal interest rate).

If the loan contract between natural persons does not stipulate or clearly stipulates the payment of interest, it shall be regarded as non-payment.