Noun and Pronoun Agreement: These/Those

The demonstrative pronouns these and those are plural pronouns, and should refer to plural nouns. Mistakes frequently occur in situations where many things are put into one group, such as a pair of shoes, or a bag of marbles. In such cases, the pronoun should agree with pair, or bag. Mistakes can also occur when an accent or dialect makes this and these sound similar; while this can be charming to hear, it is considered incorrect in formal writing.

Please move these box of books to the other table.

The pronoun should refer to the box, not the books.

Please move this box of books to the other table.

What is all these noise?

Even though there may be several sources of noise, the verb is tells the reader that the sentence should be in the singular.

What is all this noise?