【新托福ETS官方综合写作真题】- 高清高仿真PPT模考版，互动答题.pps

Toefl iBT Practice TestTPO 9 Writing Task 1
No. of Questions: 1
Begin Test
Time: approx. 30 minutes
CONTINUE
Now put on your headset
Click on CONTINE to go on
Begin reading
You have 3 minutes to read the passage.
Click to begin reading now .
Car manufacturers and governments have been eagerly seeking a replacement for the automobile's main source of power, the internal-combustion engine. By far the most promising alternative source of energy for cars is the hydrogen-based fuel-cell engine, which uses hydrogen to create electricity that, in turn, powers the car. Fuel-cell engines have several advantages over internal-combustion engines and will probably soon replace them.
One of the main problems with the internal-combustion engine is that it relies on petroleum, either in the form of gasoline or diesel fuel. Petroleum is a finite resource; someday, we will run out of oil. The hydrogen needed for fuel-cell engines cannot easily be depleted. Hydrogen can be derived from various plentiful sources, including natural gas and even water. The fact that fuel-cell engines utilize easily available, renewable resources makes them particularly attractive.
Second, hydrogen-based fuel cells are attractive because they will solve many of the world's pollution problems. An unavoidable by-product of burning oil is carbon dioxide, and car