Taking the new coronavirus antigen test as an example, the presence of two bars is generally positive, one dark and one light is weakly positive (suspected infection). The new coronavirus antigen test card is generally divided into the C area and T area, generally the presence of horizontal bars in both areas indicates the presence of the new coronavirus in the body of the tester, positive; if the two bars, one dark and the other light is weakly positive, it may be the body of the new coronavirus load is relatively low or the tester is in the latent period of the virus, or it may be a false positive. In addition, if a bar appears at C, it is negative; if no bar appears at C, it is invalid. The New Coronavirus antigen test is used for initial screening of the infected population, but its accuracy is not as good as nucleic acid testing and false positives and false negatives may occur. If the antigen test shows one dark and one light, it is recommended to review the test and have the nucleic acid test performed in time to avoid other adverse situations.