The Southwestern United States (also known as the American Southwest) is the informal name for a region of the western United States. Definitions vary a great deal and have never been standardized--and many have been proposed. For example, it might include the stretch from east of Los Angeles to El Paso, and from the Mexican border to south of Denver. The population for that particular definition area is around 11 million people, with over half that in the state of Arizona. The largest metropolitan areas are Phoenix (with a population over 4 million people) and Las Vegas (about 2 million); other significant population centers in the Southwest are Albuquerque, El Paso, and Tucson. 

Most of the area was part of the Viceroyalty of New Spain in the Spanish Empire before becoming part of Mexico. European settlement was almost non-existent outside New Mexico in 1848, when it became part of the United States through the Treaty of Guadalupe Hidalgo; far southern Arizona was added in the later Gadsden Purchase. 

The geography of the region is mainly made up by four features: the Mojave, Sonoran, and Chihuahuan Deserts, and the Colorado Plateau; although there are other geographical features as well, such as a portion of the Great Basin Desert. The deserts dominate the southern and western reaches of the area, while the plateau (which is largely made up of high desert) is the main feature north of the Mogollon Rim. The two major rivers of the region are the Colorado River, running in the northern and western areas, and the Rio Grande, running in the east, north to south. QUESTIONS:

Q1:
1. Is the American Southwest the region's official name?
2. Is it most formal to refer to the region as the American Southwest?
3. 
Q2:
1. What is the more formal name of the American Southwest?
2. What official name does the American Southwest ahve?
3. 
Q3:
1. Does the American Southwest cover a definitive area?
2. Does what is called the American Southwest have rigid boundaries?
3. 
Q4:
1. Is Arizona generally included in the American Southwest?
2. Is Arizona usually considered to be a part of the American Southwest?
3. 
Q5:
1. What is the largest city in the American Southwest?
2. Which city is the biggest one in the American Southwest?
3. 
Q6:
1. How many people live in Phoenix?
2. What is the population of Phoenix?
3. 
Q7:
1. Are there deserts in the American Southwest?
2. Does the Southwestern United States contain deserts?
3. 
Q8:
1. What is one of the deserts in the American Southwest?
2. What desert is one of the ones that can be found in the Southwestern United States?
3. 
Q9:
1. Does the Southwestern United States contain any bodies of water?
2. Are there large water sources in the American Southwest?
3. 
Q10:
1. Are there any big rivers in the Southwestern United States?
2. Does the American Southwest contain any big rivers?
3. 
Q11:
1. How many big rivers are there in the American Southwest?
2. What is the number of sizeable rivers in the Southwestern Untied States?
3. 
Q12:
1. What rivers are in the Southwestern United States?
2. What are the names of the American Southwest's rivers?
3. 
Q13:
1. In what year was most of the American Southwest incorporated into the United States?
2. When did most of the American Southwest become a part of the United States?
3. 
Q14:
1. What allowed the American Southwest to become a part of the United States?
2. What granted the Southwestern United States entry into the country
3. 
