be supposed to do

[Progress]

Hello. I would like to ask native speakers of English the following questions

People of other nations think that Americans speak frankly and plainly. Americans are supposed to say what they mean and mean what they say.

If you paraphrase it, is it that #1 Americans are supposed to say what they mean and are supposed to mean what they say? And #2 Americans are thought, by other peoples, to say what they really want to say and are thought that what they say is true?

#3 What is the same usage of are supposed to do among the three choices?
1. You are supposed to take off your shoes in this room. Required?
2. I am supposed to see the doctor at four this afternoon. Intended?
3 He is supposed to be a good teacher of English. Firmly Believed?

I think this case No. 3

Thank you very much

[Donbelid]

Be supposed to... means be expected to...

For example if you have an appointment with a doctor (at 10 O'clock), the doctor expects you to be on time, so you are supposed to be in his office at 10.

Sometimes "be supposed to" is like "should":
I'm supposed to take two pills a day.

[Teia]

Hello. I would like to ask native speakers of English the following questions

People of other nations think that Americans speak frankly and plainly. Americans are supposed to say what they mean and mean what they say.

If you paraphrase it, is it that #1 Americans are supposed to say what they mean and are supposed to mean what they say? And #2 Americans are thought, by other peoples, to say what they really want to say and are thought that what they say is true?

#3 What is the same usage of are supposed to do among the three choices?
1. You are supposed to take off your shoes in this room. Required?
2. I am supposed to see the doctor at four this afternoon. Intended?
3 He is supposed to be a good teacher of English. Firmly Believed?

I think this case No. 3

Thank you very much

In my opinion firmly believed is correct or ,even better , expected.

Americans are supposed / expected to say what they mean and are supposed/ expected to mean what they say.

[Progress]

Thanks Donbelid and Teia

I would like to know #1 the differences between Americans are supposed to say what they mean and the other three choices and #2 the meaning of mean what they say.

Thank you very much.

[Donbelid]

It means: People of the world expect Americans to say what they are determined to do and be determined in doing what they say.

to mean, here, means "to be serious".