Nevertheless is an adverb that tells the reader that something happened even though there is something that might have stopped it from happening. Here are some example sentences with nevertheless:
The math test was very difficult; nevertheless, she earned a good grade. [=Because the test was very difficult, she might have earned a bad grade, but she didn't.]
She never liked reading about economics, but the book was interesting nevertheless. [=She didn't think the book about economics would interest her, but it did.]
Every time he tried, he failed. Nevertheless, he did not quit trying. [=He could have quit trying because of his failures, but he didn’t.]
He had three friends help him with the job. Nevertheless, it took them all day to finish. [=The help of three friends could have made the job go faster, but it didn't.]
The traffic was very bad, but she arrived at work on time nevertheless. [=Because of the bad traffic she could have arrived late, but she didn't.]
Some words and phrases that can be used in place of nevertheless are nonetheless, even so, however, and in spite of that.