The principal lender refers to the person who is directly responsible for repayment, regardless of the loan ratio. For example, Zhang Si and his wife bought a house, and the borrower was Zhang Si, but the actual repayment can only be Zhang. Zhang San is responsible for the monthly mortgage repayment, and Zhang San is called the main lender.

The word "Mortgage" is a cantonese transliteration of the English word "mortgage", which refers to obtaining bank loans with real assets such as real estate or securities and contracts as collateral, and repaying the principal and interest in installments according to the contract. After the loan is paid off, the bank returns the collateral. Mortgage means that the mortgagor takes the mortgage beneficiary of property right transfer as the repayment guarantee. After the mortgagor pays off the loan, the beneficiary immediately transfers the property rights involved to the mortgagor. In this process, the mortgagor enjoys the right to use the property.