traducir MUST: deber, tener que, deber, tener que, deber de, deber, deber. Más información en el diccionario inglés-español. I think "may not" is almost = must not as you use "may not" for saying that something is not possible.! It's not the fact that may needs to be always a formal way to ask or say things, it also stands for possibility. They may not include spaces. It's a possibility for a thing not to happen. They must not include spaces. In particular, they MUST only be used where it is actually required for interoperation or to limit behavior which has potential for causing harm (e.g., limiting retransmisssions) For example, they must not be used to try to impose a particular method on implementors where the method is not required for interoperability. 7. How to use them. Must means 'Do it!' If you don't do it, you will be in trouble. You must listen to the teacher. Mustn't means 'Don't do it!' If you do it, you will be in trouble. We mustn't forget our books. Use the infinitive without to after must and mustn't. Children must respect their parents. Parents must take care of their children. We can use modal verbs for deduction - guessing if something is true using the available information. The modal verb we choose shows how certain we are about the possibility. This page focuses on making deductions about the past. must have. We use must have + past participle when we feel sure about what happened. rVw3XGN.

use of must and must not