PHÂN BIỆT IN THE END / AT THE END

IN THE END       means finally, after all.
                        It suggests that something happened after a lot of changes, problems or  uncertainty.
                        Are you going to marry her in the end?


AT THE END       simply refers to position at the end of something.
                         at the end of the month, at the end of the film, at the end of May.

                        The opposite of 'at the end' is 'at the beginning'  of something.

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