С объяснением. When we came home from grandma,s yesterday, our room (1) ... (be) in terrible mess.We (2)...(leave) the window oven and the wind (3) ... (break) the vase. There (4) ... (be) a lot of small pieces of glass on the carpet,the wind (5) ... (throw) them there.The carpet itself (6) ... (be) absolutely wet.

1. Helen had been trying to find her textbook for two hours but she had failed.
Explanation: In this sentence, we use the past perfect continuous tense because "trying to find her textbook" was a continuous action that started in the past before another past action (failing to find the textbook).

2. Sofi had been writing the essay for three hours when Matt came.
Explanation: Here, we use the past perfect continuous tense because "writing the essay" was a continuous action that started in the past and continued up until another past action (Matt came).

3. Had it been snowing all night long?
Explanation: In this case, we use the past perfect continuous tense because "snowing all night long" was a continuous action that started in the past and continued up until the present (when the question is being asked).

4. How long had they been cooking the dinner before the girls started helping them?
Explanation: Here, we use the past perfect continuous tense because "cooking the dinner" was a continuous action that started in the past and continued up until another past action (the girls started helping them).

5. Mary had been working for 25 years in the company before she retired.
Explanation: In this sentence, we use the past perfect continuous tense because "working for 25 years" was a continuous action that started in the past and continued up until another past action (she retired).

6. They had been building the house for 5 years before they moved in.
Explanation: Here, we use the past perfect continuous tense because "building the house" was a continuous action that started in the past and continued up until another past action (they moved in).

7. Mark had been driving the car for 20 hours when he almost got into the accident.
Explanation: In this case, we use the past perfect continuous tense because "driving the car" was a continuous action that started in the past and continued up until another past action (he almost got into the accident).

8. When she entered the restaurant, the administrator told her that the man had been waiting for her for an hour already.
Explanation: Here, we use the past perfect continuous tense because "waiting for her for an hour" was a continuous action that started in the past and continued up until another past action (she entered the restaurant).

9. After I had been walking for an hour, I decided to have a rest.
Explanation: In this sentence, we use the past perfect continuous tense because "walking for an hour" was a continuous action that started in the past and continued up until another past action (deciding to have a rest).

10. Mary could see that the child had been crying for some time.
Explanation: Here, we use the past perfect continuous tense because "crying for some time" was a continuous action that started in the past and continued up until another past action (Mary could see).

11. That was the factory where my father worked. He had been working there for fifteen years.
Explanation: In this case, we use the past perfect continuous tense because "working there for fifteen years" was a continuous action that started in the past and continued up until another past action (he worked there).

1. The lesson starts at 10 o'clock.
Explanation: The verb "to start" is in the base form because it is an action that happens in the present.

2. What time does the play start?
Explanation: The verb "does" is used to form the question in the present simple tense. "Start" is in the base form because it is an action that happens in the present.

3. What are you doing tonight?
Explanation: The verb "are" is used with the subject "you" to form the question in the present continuous tense. "Doing" is in the base form because it is an action happening in the present continuous tense.

4. Look at the sky! It is snowing.
Explanation: The verb "is" is used with the subject "it" to form the sentence in the present continuous tense. "Snowing" is the present participle form of the verb "to snow."

5. I am leaving tomorrow morning.
Explanation: The verb "am" is used with the subject "I" to form the sentence in the present continuous tense. "Leaving" is the present participle form of the verb "to leave."

6. Deborah is having a birthday party on Saturday.
Explanation: The verb "is" is used with the subject "Deborah" to form the sentence in the present continuous tense. "Having" is the present participle form of the verb "to have."

7. Hurry up! The film starts in 10 minutes.
Explanation: The verb "starts" is in the base form because it is an action that happens in the present.

8. Where are you going on holiday?
Explanation: The verb "are" is used with the subject "you" to form the question in the present continuous tense. "Going" is in the base form because it is an action happening in the present continuous tense.

9. I'm sure, he will agree to do it.
Explanation: The verb "will" is used to express future certainty. "Agree" is in the base form.

10. OK, I will help him.
Explanation: The verb "will" is used to express future actions. "Help" is in the base form.

11. Sam is seeing his relatives tonight.
Explanation: The verb "is" is used with the subject "Sam" to form the sentence in the present continuous tense. "Seeing" is the present participle form of the verb "to see."

12. I think we will meet next week.
Explanation: The verb "will" is used to express future actions. "Meet" is in the base form.

13. I'm hungry. I will make myself a sandwich.
Explanation: The verb "will" is used to express future actions. "Make" is in the base form.

14. Annie will be three years old next month.
Explanation: The verb "will" is used to express future actions. "Be" is in the base form because it is a state verb.

15. Have you decided where to go on holiday? Yes, I will travel around Europe.
Explanation: The verb "will" is used to express future actions. "Travel" is in the base form.

16. It's lovely. I will buy this dress!
Explanation: The verb "will" is used to express future actions. "Buy" is in the base form.

17. What time does the bus stop?
Explanation: The verb "does" is used to form the question in the present simple tense. "Stop" is in the base form because it is an action that happens in the present.

18. Look at that car! Oh no! It is hitting the lamppost!
Explanation: The verb "is" is used with the subject "it" to form the sentence in the present continuous tense. "Hitting" is the present participle form of the verb "to hit."

19. Would you like something to drink? I will have juice, please.
Explanation: The verb "will" is used to express future actions. "Have" is in the base form.

20. I don't understand this exercise, Dad. OK, Peter I will help you.
Explanation: The verb "will" is used to express future actions. "Help" is in the base form.

21. The Ting Tings will play a concert at Wembley Stadium. I know. I have already bought a ticket.
Explanation: The verb "will" is used to express future actions. "Play" is in the base form.

22. It is Friday.
Explanation: The verb "is" is used to describe a state. "Friday" doesn't have a verb.

23. She will become a dentist in the future.
Explanation: The verb "will" is used to express future actions. "Become" is in the base form.

24. My granny will come in the evening.
Explanation: The verb "will" is used to express future actions. "Come" is in the base form.

25. We will leave as soon as the taxi arrives.
Explanation: The verb "will" is used to express future actions. "Leave" is in the base form.

26. Costas and I will get married in April.
Explanation: The verb "will" is used to express future actions. "Get married" is in the base form.

27. What do you want for lunch? I think I will have chicken and some salad.
Explanation: The verb "will" is used to express future actions. "Have" is in the base form.

28. The comedy will start in 20 minutes.
Explanation: The verb "will" is used to express future actions. "Start" is in the base form.

29. I expect she will come early.
Explanation: The verb "will" is used to express future actions. "Come" is in the base form.

30. Can I help you with your bags?
Explanation: The verb "can" is used to ask for permission. "Help" is in the base form.

31. Shall we go for a picnic tomorrow?
Explanation: The verb "shall" is used to make suggestions. "Go" is in the base form.

32. I don't really like cheese. OK, I will not buy any then.
Explanation: The verb "will" is used to express future actions with negation. "Buy" is in the base form.

33. I probably will buy a new bike. I'm not sure yet.
Explanation: The verb "will" is used to express future actions. "Buy" is in the base form.