1. Let's meet at the car at six.

2. Let's meet near the car at six.
3. Let's meet inside the car at six.
[You mean #1 is #2. #1 doesn't mean #3. Is that right?]

4. Let's meet at the bus at six.
5. Let's meet near the bus at six.
6. Let's meet inside the bus at six.
[You mean #4 is #5. #4 doesn't mean #6. Is that right?]

7. Let's meet at the park at six.
8. Let's meet near the park at six.
9. Let's meet inside the park at six.
[What about these three sentences? Here, #7 doesn't mean #8. #7 means #9. Is that right? Do you have any logical theory about the difference between these three sentences and the previous example sentences?

1 and 2, yes

3 maybe -- if both have keys if the car is locked

4 and 5. yes
6 not a normal expression, no, but possible if the bus waits for both to get on board

7, 8, and 9. All are OK.

Any logic here depends on what it is.

Yes, you are correct. In sentences 1-3, there is a distinction between the meanings. Let's break it down:

1. "Let's meet at the car at six." This suggests meeting at the specific location of the car at the designated time.
2. "Let's meet near the car at six." This implies meeting in proximity to the car, but not necessarily at the exact location of the car. It could be nearby or close to the car.
3. "Let's meet inside the car at six." This means meeting inside the car itself at the designated time.

Similarly, in sentences 4-6:

4. "Let's meet at the bus at six." This implies meeting at the specific location of the bus at the designated time.
5. "Let's meet near the bus at six." This means meeting in proximity to the bus, but not necessarily at the exact location of the bus.
6. "Let's meet inside the bus at six." This suggests meeting inside the bus itself at the designated time.

Now, regarding sentences 7-9:

7. "Let's meet at the park at six." This suggests meeting at the specific location of the park at the designated time.
8. "Let's meet near the park at six." This implies meeting in proximity to the park but not necessarily at the exact location. It could be nearby or close vicinity to the park.
9. "Let's meet inside the park at six." This means meeting within the boundaries of the park itself at the designated time.

The key difference between these sets of sentences lies in the preposition used ("at," "near," or "inside") which indicates the level of proximity and location. By using different prepositions, the meaning and implications of the sentences change.