将下面改写的学术、精炼一点Furthermore column 3 and column 4 add control variables on the basis of the above and the coefficient of HIC to efficiency is positive and it passes the significance test of 1 which means

Moreover, by including additional control variables in column (3) and column (4), the positive coefficient of HIC on efficiency is statistically significant at the 1% level. This suggests that the synergistic development of human capital and artificial intelligence contributes to enhancing the effectiveness of resource allocation in enterprises.