Difference between past present and future is an example of ?

The difference is that the past is something that happened previously for example Maria singing, present is what is happening at this moment for example Juan is eating and the future is something that will happen after, for example, Lucy will play.

They are verb tenses

racism and segregation.

in his book, the riddle of the rosetta stone, james giblin talks about how there was a young british polymath and physician named thomas young who made a lot of advances on the deciphering of the rosetta stone. he says that even though young made a lot of mistakes because he was working under false assumptions, he also made huge contributions like deciphering three out of the seven symbols (more than anyone else before him). young published his findings and continued his good work but he wasn't able to progress much further due to some unfavorable situations, he still laid the basis for many other scholars and of course for the man who has been generally known to have deciphered it, jean-françois champollion