/ There are an ocean of flowers in the Pacific Ocean.’ I saw a similar sentence in the Internet. What of the sentences I saw? Is the grammar correct? Are ocean of flowers plural?

If it is singular, then the verb should be ‘is’ – There is an ocean of flowers.

Apparently the writer consider ‘an ocean of flowers’ a plural subject as (on this page) the verb are! Why do some phrases start with ”an ocean of…’?

Thank you for your feedback.

What exactly is the meaning of the phrase “we pay taxes only when we don’t spend money on our goods and services”?