14. Our car is bigger than ______
Correct answer: C. them
Explanation: "Them" is used as a comparison, in this case, referring to "their car" (the car they own).

15. Whose dictionary is this? - It's ______
Correct answer: B. theirs
Explanation: "Theirs" is the correct possessive pronoun to indicate that the dictionary belongs to them.

16. Junko has eaten her lunch already, but I'm saving ______ until later.
Correct answer: C. mine
Explanation: "Mine" is the correct possessive pronoun referring to the speaker’s lunch.

17. We gave them ______ telephone number, and they gave us ______
Correct answer: C. ours, theirs
Explanation: "Ours" refers to the speaker’s telephone number, and "theirs" refers to the telephone number of the other person.

18. ______ computer is a Mac, but ______ is a PC.
Correct answer: B. Yours, mine
Explanation: "Yours" refers to the other person's computer, and "mine" refers to the speaker's computer.

19. You can't have any chocolate! It's ______
Correct answer: A. mine
Explanation: "Mine" is the possessive pronoun referring to the chocolate that belongs to the speaker.

20. Was ______ pencil broken? Can I borrow ______?
Correct answer: B. Your, mine
Explanation: "Your" refers to the other person's pencil, and "mine" refers to the speaker’s pencil.

21. Is the grammar book expensive? ______
Correct answer: B. yours
Explanation: "Yours" is the possessive pronoun referring to the grammar book owned by the other person.

22. Jody has lost ______ book.
Correct answer: A. mine
Explanation: "Mine" is the possessive pronoun indicating the book that belongs to the speaker.

23. This bird has a broken ______ wing.
Correct answer: C. hers
Explanation: "Hers" refers to the bird's wing, in this case, belonging to the bird.

24. My telephone is out of order, but ______ is working.
Correct answer: C. his
Explanation: "His" is used here to refer to the telephone of the male person.

25. These grammar books are different. ______ has 278 pages, but ______ has only 275 pages.
Correct answer: C. Yours, mine
Explanation: "Yours" refers to the other person's books, and "mine" refers to the speaker's book.

Exercise 18:

1. My younger sister lost (she's/her) phone on the bus this morning.
   Correct answer: her

2. The students are keeping (their/theirs) eyes on smartphones now.
   Correct answer: their

3. I like learning online on (my/mine) computer.
   Correct answer: my

4. I sometimes send voice messages to (me/my) friends.
   Correct answer: my

5. What's (you/your) favorite social media application?
   Correct answer: your

6. My camera is on the table. (Your/Yours) is on the shelf.
   Correct answer: Yours

7. Trang is a neighbor of (my/mine) (He's/His) duty is to hold video conferences.
   Correct answer: my, His

8. Is (his/him) major English? Don't let this camera focus on (ours/our) foreheads.
   Correct answer: his, our

Exercise 19:

1. I think language barriers (disappear) ______ in 30 years.
   Correct answer: will disappear

2. Some people usually (take) ______ a long time to respond to a message.
   Correct answer: take

3. Learning English can help us overcome difficulties when (live) ______ in other countries.
   Correct answer: living

4. By (use) ______ social networks, people can keep in touch with others.
   Correct answer: using

5. What is people's top concern when it (come) ______ to messaging applications?
   Correct answer: comes

6. Developers of ConnectABC commit to (update) ______ the application twice a month.
   Correct answer: updating

7. I can't leave the classroom until my teacher (give) ______ me the assignment.
   Correct answer: gives

8. Mary gave me (you/yours) sh ______ advice without any complaints.
   Correct answer: yours

9. Emoji (become) ______ integral to digital communication in the past few decades.
   Correct answer: have become

10. Robots can (listen) ______ to people's problems and (give) ______ them useful advice.
    Correct answer: listen, give