usage of devoir
This is one of the many examples that i am not able to get the exact meaning of .... like we know in french must = should , and devoir has various meanings like must, should, be allowed to ...... so, if we write "je ne dois pas me reveiller tard." so does this mean that i should not get up late or i am not allowed to get up late or i must not get up late(considering some consequences as a result) ?????
It does not mean 'i am not allowed to get up late'. I believe that of the three choices you mentioned, the last one is most accurate - 'must not'. 'Dois', which is a present tense verb, does not mean 'should' - it means 'must'. If you want to say 'should', you should use the form 'devrais', which is the conditional tense. Here: I should - je devrais. You singular should - tu devrais. He should - il devrait. (All three of these are pronounced dev-ray). We should - nous devrions. You plural should - vous devriez. They should - devraient (also pronounced dev-ray).
See it as two separate clauses/phrases, this will help clarify the intention. The first phrase sets up the meaning for the second. First phrase: "je ne dois pas" - I must not. Can't be anything else really - but Duo maybe has you confused because of the way it translates "je dois" as "I have to". Read it like it is: "I must not". Second phrase: "me reveiller tard" - get myself up late
I like your translation. I am going to delete my post. I think yours is better.
One of the reasons that automated language translation is not well implemented is that not all words in one language have a one to one correspondence with words in a second language.