Hello Maciel. Brag has a negative meaning and is when someone speaks about his or her accomplishments with an exaggerated pride. Boast is normally used in a positive sense and is when someone speaks about his or her achievements showing a sense of accomplishment. For example... She bragged about winning the race to all of her competitors, making them feel bad. She boasted about being able to run the race in under two hours, because she was very happy about her achievement. I hope that helps!

As an intransitive verb, both 'boast' and 'brag' are similar and negative, with brag being more common. Rarer, but 'boast' can also be a transitive verb, which isn't negative. Switzerland boasts some of the world's best scenery. The museum boasts an impressive collection of Impressionists.

The meaning is basically the same. But "boast" is an older word. "Brag" is more common now, in my opinion.

In my opinion, they are very similar, and both have a negative connotation -- the person is excessively proud of his/her accomplishments and needs to tell everyone about them.

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