Answer:
1. Even though she was pregnant with her first child, Sacagawea was chosen to accompany them on their mission. Lewis and Clark believed that her knowledge of the Shoshone language would help them later in their journey.
2.Sacagawea and her husband lived among the Hidatsa and Mandan Indians in the upper Missouri River area (present-day North Dakota). In November 1804, an expedition led by Meriwether Lewis and William Clark entered the area. ... Lewis and Clark met Charbonneau and quickly hired him to serve as interpreter on their expedition.
3.While they were crossing the Rockies, several Indian tribes helped the Corps of Discovery by offering food and comfort. In August of 1805, Sacajawea recognized the landscape where they were traveling, so the explorers were on the lookout for a Shoshone Indian camp.
4. In June 1805, working with descriptions given them by Native Americans, they discovered the Great Falls of the Missouri, making them the first Americans to see them. Lewis described the awe-inspiring sight: I had proceded on this course about two miles.