In English, there are four demonstratives: this, these, that, those
To Show Distance
Demonstratives are classified in two dimensions, near and far. This (singular) or these (plural) are used for near. That (singular) or those (plural) are used for far.
|Ex. I want this toy.
|Ex. I want that toy.
|Ex. I want these toys.
|Ex. I want those toys.
To Specify a Particular Noun
Demonstratives point out or specify a particular noun.
Ex. I want that toy!
In this sentence, the pronoun that points out (or demonstrates) a specific toy, distinguishing it from all other toys. Demonstratives used before a noun to distinguish it from other nouns function like adjectives.
Ex. Emily will win that prize.
Ex. Those rings are nice, but Maria wants to buy these rings.
To Replace Nouns
Demonstratives can also act as pronouns, replacing the subject of the sentence.
Ex. That is the best hot dog ever!
Ex. Those are not very good steaks.
Ex. That is a dangerous cliff.
In the first example, that is acting like a regular pronoun. However, it is still demonstrative because it tells us (or demonstrates) which hot dog is the best (that one!).
As with all pronouns, sometimes you need to depend on context to determine a demonstrative’s antecedent.
Ex. Some tiles are loose. Don’t step on those!
Without the context of the first sentence, it’s impossible to determine what exactly those refers to in the next sentence. Using those made it clear that the tiles not to be stepped on are the loose ones.
When you use a demonstrative, be sure its meaning is clear. In the first example below, it’s not clear what this refers to. In the second example, the meaning is clear because we’ve changed this from a stand-alone demonstrative pronoun to a demonstrative adjective modifying a noun.
Ex. Ambiguous This shows an upward trend in consumption.
Ex. Clear This graph shows an upward trend in consumption.