Grammar exercise focusing on using "this" and "these" correctly in sentences.

Let's solve the exercise step by step. The task is to choose between "this" (singular) or "these" (plural) depending on the noun that follows.

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Rules:

- Use "this" for singular nouns.
- Use "these" for plural nouns.

Now, let’s go through each sentence:

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1. Is ________ my drink?
- "drink" is singular → this
✔ Is this my drink?

2. ________ aren’t my trainers.
- "trainers" is plural → these
✔ These aren’t my trainers.

3. Is ________ an interesting museum.
- "museum" is singular → this
✔ Is this an interesting museum?

4. ________ are new bikes.
- "bikes" is plural → these
✔ These are new bikes.

5. ________ is my house.
- "house" is singular → this
✔ This is my house.

6. ________ is a hill.
- "hill" is singular → this
✔ This is a hill.

7. ________ are donkeys.
- "donkeys" is plural → these
✔ These are donkeys.

8. What is ________?
- "is" indicates a singular subject → this
✔ What is this?

9. Did you drop ________?
- No specific noun given, but context suggests something dropped — could be singular or plural. However, since it's a common question and no plural is implied, we assume singular → this
✔ Did you drop this?

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✔ Final Answers:

1. this
2. These
3. this
4. These
5. This
6. This
7. These
8. this
9. this

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Summary:

- Use "this" when referring to one thing.
- Use "these" when referring to more than one.

Let me know if you'd like a version with explanations in your native language!