to be supposed; a(an)/any

[Tapies]

Hi, please can you tell me:

a)
Is there a difference between the following sentences?
To be supposed to do something. / To be to do something.

b)
You can see a car. (not some car)
Can you see a car? can I also say Can you see any car?
or must there only be either Can you see a car or Can you seeany cars?

Thank you, T.

[Tdol]

If you are supposed to do something, you are expected to/should do it but probably won't. If you are to do something, you have arranged or been instructed to do something and will do it.


Can you see any car?
This is like 'any car at all'.