Explanation:

  Before there were cars or very good railroads, which are special roads for trains, most transportation in the United States relied on (or used) rivers. Using boats on rivers was the fastest way to move people and goods (or products, like food, medicine, and tools) from one place to another. The United States has many long rivers that were used for transportation in those early days. This was especially true for the country’s longest river, the Missouri River, and its second-longest river, the Mississippi River.

  The Missouri River played an important role (or part) in the exploration of the western United States. This exploration was an effort to try to learn what the land was like in the West. In 1803, President Thomas Jefferson asked Captain Meriwether Lewis to explore the Missouri River and find out whether it could be used to transport (or move) things across North America. At that time, no one knew where the Missouri River went, but everyone wanted to find a river that would move things from the east to the west.

  Captain Meriwether Lewis chose a team of 33 people to go with him, including a partner, William Clark. Their journey (or long trip) became known as the Lewis and Clark expedition. It lasted from 1803 to 1806. It was a difficult and dangerous journey into uncharted (or unmapped and unknown) land. The men suffered from disease (or illnesses), hunger, cold weather, and fights against the Native Americans (or American Indians), but only one man died during the expedition. This is a testament to William and Clark’s leadership, or a sign that their leadership was very good and strong.

  Lewis and Clark wrote about everything they did and saw in journals (or small books). They described many plant and animal species (or types of plants and animals) that no one had seen before. They discovered that the Missouri River did not go all the way to the Pacific Ocean, but they got there anyway. They established relationships with many Native American tribes (or groups). In general, the expedition was a major success and an important source of information for the United States at that time.

 

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