1.) "You must be wrong," he said. (probability)
will be:
He said I must be wrong.
and not
He said I had to be wrong.
-------------------------------------
2.) "You must appologize," he said. (external moral obligation)
will be:
He said I had to appologize.
and not
He said I must appologize.
--------------------------------------
Am I right in thinking that 'must' goes through a modal change if and only if it expresses obligation or necessity?
Please, note that I made up the sentences myself -- they might be incorrect.
Thanks.