What word in dull sublunary love from fourth stanza of John A Valediction Forbidding Mourning suggests that the discussed would be impermanent?

The word that suggests impermanence in the phrase "dull sublunary love" from the fourth stanza of John Donne's "A Valediction Forbidding Mourning" is "sublunary."

Here's why:

* Sublunary refers to the world below the moon, which was traditionally seen as the realm of change and decay. In contrast, the celestial sphere above the moon was considered eternal and unchanging.

* By calling their love "sublunary," Donne suggests that it is subject to the same limitations and impermanence as everything else in the physical world.

* This contrasts with the spiritual and eternal love he envisions, which transcends the earthly realm and therefore escapes the limitations of time.

The line itself emphasizes this contrast: "Our two souls therefore, which are one, though I must go, endure not yet a breach, but an expansion." Their love, like their souls, is not broken by physical separation but expands into a higher, more lasting realm.