What is the appropriate phrase to complete the conversation about knowing a husband for years?

The choice to complete the conversation appropriately is based on the context of confirming shared knowledge or experiences. The phrase "Haven't you?" is used when asking someone if they have had a certain experience or knowledge in the past that is expected. In the context of discussing knowing a husband for years, the speaker is likely referring to a situation where it is assumed that familiarity would exist given the duration of the relationship. This phrase invites an affirmative response and reinforces the assumption that the person should indeed be well-acquainted.

The other choices would not fit as neatly into the context of confirming shared knowledge or experiences. For instance, "Isn't it?" would suggest a confirmation about a statement rather than an inquiry about the subject’s previous experiences, while "Didn't you?" would imply questioning if someone had a specific experience in the past, which feels slightly out of place. "Shouldn't you?" also indicates obligation or expectation but does not effectively communicate the notion of shared experience in the same way that "Haven't you?" does.