What is the poet saying when he writes that “old age shall this generation waste”?

The poet is saying that people don’t live long; life is brief.

Explanation:

The phrase "old age shall this generation waste" was written in the poem Ode on a Grecian Urn, by John Keats. In this poem the poet compared the duration of a vessel with the duration of our life, unlike the vessel, which is resistant and will last for many years, our life is brief, finite and fragile, we will not last for many years , one day old age will come and end our beauty, focus and disposition. For this reason, the author says that old age will waste this generation.

the answer is:

when will (v) the books (n) be (v) due?

nouns refer to people (other than pronouns), places and things, whereas verbs describe actions and are usually part of the predicate of a sentence. finally, pronouns can work as nouns and identify the participants in speech.

in the example sentence, "will" is a verb part or auxiliary verb, "be" is an infinitive verb and "books" is a plural noun.