Talāqā portrays lines that meet or converge, while tabīn suggests that they are distinguishable and separate. Wa-aḥyānan marks alternating occasions or aspects of their appearance.
The meaning depends on a contrast: convergence ↔ separation. The image is not merely a fixed patch; the marks look connected at one point and distinct at another. Understanding this opposition helps explain why cloth inserts provide an apt visual analogy.