Which early american civilization had slaves

What is the meaning of the word checking as it is used in this sentence from the second paragraph of the passage?

Martin luther king jr often spoke of a day in the future when he hoped that his children would be judged not by their skin color but instead by their character. write a narrative essay about a moment in your life when you were judged by something other than the content of your character. use narrative techniques to develop experiencies, events, and characters

The greatest gift the sumerians gave the world was the invention of writing. the sumerians were wealthy people. they needed some way to keep track of what they owned. they began drawing pictures. they used a reed as a pen. they drew on soft pieces of clay. the soft clay was then dried in the sun. the tablet became a permanent record. later, the sumerian drawings changed into wedge-shaped symbols. this kind of writing is called cuneiform. by putting symbols together, the sumerians could write entire sentences.