DISCOVERING GRAMMAR / 9 singular plural personal possessive personal possessive 1st person I mine we ours 2nd person you yours you yours 3rd person he, she, his, hers, they theirs it its Using demonstrative pronouns Nouns can also be replaced with demonstrative pronouns . These are: singular plural this these that those This is interesting. That is not right. These are expensive. Those look delicious. Interrogative pronouns are used to ask questions. They are used at the start of a question as in the following examples: Which do you wish to take? Who is moving into that house? Whose is that pencil? Using interrogative pronouns Remember that there must be a question mark at the end.