**must-read:** Why Everyone Is Talking About Joe Bastardi Twitter's Latest Rant. Here's Where Hurricane Ian Will Go Next Meteorologt

Meaning you should know this information. Hi everybody :) could you please tell me how to express agreement and disagreement with sentences containing must and mustn´t? Hello everybody, i have read some information about this but i want to make it more clear.

Joe Bastardi on Twitter "Peaceful Friday afternoon in the office

A bbc site says that must suggests that it is the speaker who has decided that something is necessary, whereas have to and have got to suggest that somebody.

I know that mustn't have done is incorrect in british english.

Be to + infinitive = going to = must ( as the text says, be to + infitive adds demand,destiny or expectation, also necessity or obligation) i am to buy this car tomorrow. Must is a modal verb, and all modal verbs are followed by a bare infinitive: You should have received a confirmation email and you must have received a confirmation email. He must have, he could have, he might have, he would have, etc.

With must as a noun, i find a must to try exceedingly unidiomatic, which is probably why that reading didn't even cross my mind and i suspected an ungrammatical to. What is the difference between these two?