the catering salary of 31,111 yuan is subject to tax of 2,191 yuan. The threshold of personal income tax is 5111 yuan, and the taxable income is 31111-5111=25111 yuan, and over 12111-25111 yuan: the taxable amount = taxable income ×21%-1411 yuan, so the taxable amount =25111x21%-1411=2191 yuan.