“Is THIS your book?”
OR
“Is THAT your book?
What is the difference?
Both “that” and “this” refer to singular objects or people.
The difference is in how close or far away you are:
When you say, “This is my book,” you are touching your book or holding it in your hand.
When you say, “That is my book,” you are probably pointing to it, or just referring to it without seeing it.
At a party, a man says to you, “Do you see that woman in the red dress over there? That is my sister. (He is referring to someone standing away from him.)
When making introductions, you usually say, “This is my friend/colleague/spouse …” because the person that you are introducing is right next to you.
In Summary:
If you are close enough to touch something or someone, use “this.” If you have to point to something/someone too far away to touch, use “that.”
Common expressions with THAT are: “That’s impossible!” “That’s great!” “That’s terrible!”
In those cases, use “that” because it is referring to something abstract or intangible.
Imagine you hear a strange noise. You might say, “What was that?” or “What was that noise?”
THOSE vs THESE (Plurals of THAT and THIS)
When referring to more than one object or person, use the plural forms below.
The plural of THAT is THOSE.
“I love those earrings!” (Pointing to someone else’s earrings or to earrings in a store.)
“Do you like those shoes?” (Pointing to shoes in a store window.)
“Those french fries look great!” (Pointing to another person’s plate.)
The plural of THIS is THESE.
“I love these earrings!” (Holding the earrings up to your face.)
“These shoes are too tight!” (You’re pointing to or touching the shoes on your own feet.)
“These french fries are fantastic!” (You’re eating them)
At work:
THOSE:
“Did you finish looking at those reports I gave you last week?” (The person asking is referring to reports that are not in the room.)
“How did those interviews go yesterday?” (Referring to something in the past)
THESE:
“Why are there all these meetings on my calendar?” (Looking at her calendar)
“They are for summer interns. These are helpful for on-boarding.”