To determine the similar ratio of the small v343 and the large v1331 in AB form, you would typically compare the corresponding dimensions or attributes of the two objects. If v343 and v1331 are similar in shape, their ratios can be expressed as a fraction or proportion of their corresponding lengths, widths, or heights. For instance, if the lengths are in the ratio of 3:7, then the AB form would reflect this ratio accordingly. Without specific measurements, the exact similar ratio cannot be defined.