verb

 

intended be supposed to do sth: to be expected or intended to do something, especially when this does not happen

These drugs are supposed to reduce the pain.

 

must be supposed to do sth: If you are supposed to do something, the rules say that you should do it.

You're supposed to pay by the end of the month.

 

to think that something is likely to be true

I suppose that you've already heard the news?