fill the gaps with the correct verb form:
1.- i don’t think she’s worried about us. if she (be) worried, she (phone)

or something.
2.- i have an appointment at 3.30 tomorrow. if i (manage) to finish before
4.30, i (do) the shopping on my way back.

3.- tom missed his flight. he (get) to the airport on time if he

(not oversleep)

4.- if i (have) such a large house as yours, i (invite)

all my friends for the weekend.

5.- if the child (not be playing) with matches, he (not burn)

himself. now he’s in hospital.

6.- she’s so shy. if she (talk) to people, she (make) friends.

7.- so, you’re seeing terry tonight. if he (ask) you about me, (not, tell)

him i’m going out with john.

8.- if a machine (be) properly maintained, it (fail, never)

9.- we (invite) him if we (know)

his address, but he never gave it to us.

10.- unless i (have) a problem, i (bother, never) my friends.

11.- you’re very strong. if you (try) you (win) your opponent.

12.- look what you’ve done. if you (be) careful, you (not, break)

all those glasses.

13.- i was so stupid! nothing (happened) if i (not, moved)

to his flat.

14.- she’s a bit short. if he (be) taller he (can) play basket.

15.- sorry. i (lend) you the money you need if i (have) it.

16.- the bus is full up. if there (be) an empty seat, i (sit) down.

17.- why didn’t you go to the police station? if you (report) the theft, they

(can arrest) the robbers.

18.- i (leave) him a message is he (not, be) when i phone.

1. I don't think she's worried about us. If she was worried, she would have phoned or something.
- In this sentence, we are talking about a possible situation in the past. The verb form "was" is used to show the unreal situation in the past. The verb form "would have phoned" is used to show the result of that unreal situation.

2. I have an appointment at 3.30 tomorrow. If I manage to finish before 4.30, I will do the shopping on my way back.
- In this sentence, we are talking about a possible situation in the future. The verb form "manage" is used in the present tense to express the possibility of finishing before 4.30. The verb form "will do" is used to show the result of that possible situation.

3. Tom missed his flight. He would have gotten to the airport on time if he hadn't overslept.
- In this sentence, we are talking about a possible situation in the past. The verb form "would have gotten" is used to express the unrealized possibility of getting to the airport on time. The verb form "hadn't overslept" is used to show the unrealized action in the past.

4. If I had such a large house as yours, I would invite all my friends for the weekend.
- In this sentence, we are talking about a hypothetical situation in the present. The verb form "had" is used to express the unrealized situation of having a large house. The verb form "would invite" is used to show the result of that hypothetical situation.

5. If the child wasn't playing with matches, he wouldn't have burned himself. Now he's in the hospital.
- In this sentence, we are talking about a possible situation in the past. The verb form "wasn't playing" is used to express the unrealized situation of not playing with matches. The verb form "wouldn't have burned" is used to show the result of that possible situation.

6. She's so shy. If she talked to people, she would make friends.
- In this sentence, we are talking about a possible situation in the present. The verb form "talked" is used in the present tense to express the unrealized action of talking to people. The verb form "would make" is used to show the result of that possible situation.

7. So, you're seeing Terry tonight. If he asks you about me, don't tell him I'm going out with John.
- In this sentence, we are talking about a possible situation in the future. The verb form "asks" is used in the present tense to express the possible action of asking about me. The verb form "don't tell" is used to give a directive or advice in that possible situation.

8. If a machine is properly maintained, it never fails.
- In this sentence, we are talking about a general truth or fact. The verb form "is" is used in the present tense to express the condition of being properly maintained. The verb form "never fails" is used to show the result of that condition.

9. We would invite him if we knew his address, but he never gave it to us.
- In this sentence, we are talking about a hypothetical situation in the present. The verb form "knew" is used to express the unrealized situation of knowing his address. The verb form "would invite" is used to show the result of that hypothetical situation.

10. Unless I have a problem, I never bother my friends.
- In this sentence, we are talking about a general habit or behavior. The verb form "have" is used in the present tense to express the condition of having a problem. The verb form "never bother" is used to show the result of that condition.

11. You're very strong. If you try, you will win your opponent.
- In this sentence, we are talking about a possible situation in the future. The verb form "try" is used in the present tense to express the possible action of trying. The verb form "will win" is used to show the result of that possible situation.

12. Look what you've done. If you were careful, you wouldn't have broken all those glasses.
- In this sentence, we are talking about a possible situation in the past. The verb form "were" is used to express the unrealized situation of being careful. The verb form "wouldn't have broken" is used to show the result of that possible situation.

13. I was so stupid! Nothing would have happened if I hadn't moved to his flat.
- In this sentence, we are talking about a possible situation in the past. The verb form "hadn't moved" is used to express the unrealized action of not moving to his flat. The verb form "wouldn't have happened" is used to show the result of that possible situation.

14. She's a bit short. If he were taller, he could play basketball.
- In this sentence, we are talking about a hypothetical situation in the present. The verb form "were" is used to express the unrealized situation of being taller. The verb form "could play" is used to show the result of that hypothetical situation.

15. Sorry. I would lend you the money you need if I had it.
- In this sentence, we are talking about a hypothetical situation in the present. The verb form "had" is used to express the unrealized situation of having the money. The verb form "would lend" is used to show the result of that hypothetical situation.

16. The bus is full up. If there were an empty seat, I would sit down.
- In this sentence, we are talking about a hypothetical situation in the present. The verb form "were" is used to express the unrealized situation of there being an empty seat. The verb form "would sit" is used to show the result of that hypothetical situation.

17. Why didn't you go to the police station? If you reported the theft, they could have arrested the robbers.
- In this sentence, we are talking about a possible situation in the past. The verb form "reported" is used to express the possible action of reporting the theft. The verb form "could have arrested" is used to show the result of that possible situation.

18. I left him a message, but he wasn't there when I phoned.
- In this sentence, we are talking about a real situation in the past. The verb form "wasn't" is used to show the condition of him not being there. The verb form "phoned" is used to show the action in the past.

Note: It is important to mention that these answers are based on the context and grammar rules. The verb forms used may vary depending on the specific grammar tense being taught in the classroom.