The sentence 'Is there a box of chocolates on the table?' should be rewritten in plural form as 'Are there boxes of chocolates on the table?'. The change from 'is' to 'are' is necessary to maintain correct subject-verb agreement with the new plural subject 'boxes'.
To rewrite the sentence "Is there a box of chocolates on the table?" using the plural forms, the sentence would become "Are there boxes of chocolates on the table?". When changing from singular to plural, the singular noun 'box' is changed to 'boxes', and to agree with this plural subject, the singular verb 'is' must change to 'are'. Additionally, we keep 'chocolates' in plural form since in the original, 'chocolate' is uncountable and typically treated as plural when referring to multiple confections or types in a box.