Tham khảo tài liệu 'the complete guide to the toefl ibt test part 3', ngoại ngữ, toefl - ielts - toeic phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Speaking Section 769 Notes Now get ready to answer the question. The woman gives her opinion of the notice written by the Dean of Education. Explain her opinion and discuss the reasons she gives for having this opinion. I Preparation Time 30 Seconds I Response Time GO Seconds Practice 770 Section 3 Practice Test 1 Task 4 Read the following passage about airships. You will have forty-five seconds in which to read the passage. Begin reading now. Unlike helicopters and airplanes lighter-than-air craft depend on buoyant gases hydrogen and helium to make them fly. Because of these gases they rise into the air. Powered lighter-than-air craft have engines and fins and rudders just like airplanes so their pilots can control the speed and direction of their flight. There are two main types of powered lighter-than-air craft rigid airships and nonrigid airships. Rigid aircraft have internal frames made of aluminum that s why they are called rigid. The first one of these was built in 1900 by a German engineer named Count Zeppelin. Rigid airships are therefore sometimes called zeppelins. These long cigar-shaped ships were filled with hydrogen which made them very dangerous. When hydrogen combines with oxygen it can burn violently. The other type of lighter-than-air craft is the nonrigid airship. These airships are also called blimps. Blimps have no internal skeleton no internal structure. They are merely fabric envelopes. It is the buoyant gas that gives them their shape. They are fatter and much much shorter in length than the old zeppelins. Blimps are filled with helium which is a nonflammable gas and so they are much safer than rigid airships. Unlike rigid zeppelins blimps are still a fairly common sight in our skies especially during important sporting events. Now listen to a discussion about airships. Q Speaking Section 771 Notes Now gel ready to answer the question. The professor and the students discuss two airships the blimp Columbia and the zeppelin Hindenburg. Using .
