1. Poor management， outdated technology， competition from overseas， and steel's replacement to materials like aluminum and fiber-reinforced plastics has all been cited as causes for the declining of the United States steel industry.

　　2. One noted economist has made a comparison of the Federal Reserve with an automobile as racing through a tunnel， bounce first off one wall， then the other.

　　3. In the late seventh century， in a dispute about if the Prophet Muhammad's son-in-law， Ali， should carry on to be the fourth caliph， Muhammad's successor， Islam split in two branches， the Sunnis and the Shiites.

　　4. Because of natural gas are composed most in methane， a simply hydrocarbon， vehicles powered by natural gas emits fewer of certain pollutants than the burning of gasoline or diesel fuel.

　　5. The brochure notes in the seminar the importance that communication is a two-way process will be emphasized.

　　6. A grow number of farm families while the first decades of the nineteenth century begin to specialize in the production of grain or cotton and using the cash proceeds from selling its crops for buying necessities.

　　7. Prompt by new evidences that the health risk posed by radon gas is far serious than was previously thought， property owners are advised by authorities to test all dwellings below the third floor for radon gas and making repairs as need.

　　8. In terms of physics， the characteristic feature of the roller coaster is the car's potential energy， gained through their being lifted by a chain drive through the Earth's gravity to the top of the first drop， have been converted to kinetic energy by the time the ride ends.