The sheepskin raft (羊皮筏), the oldest ferry tool along the Yellow River in Northwest China, boasts a history of nearly 2,000 years. The airbag of the raft is made of a whole sheepskin and undergoes many processes including heating     1     (remove) hair, soaking in salty oil, sewing, drying and blowing. Then the airbags are fastened to a wooden stand, enabling its use for transporting people and goods     2     the water.

It is said that the largest sheepskin raft in old times     3     (consist) of more than 600 sheepskin airbags, with an impressive length of 22 meters and a     4     (wide) of 7 meters. It was capable of carrying around 30 tons of goods and drifting over 200 kilometers in one day.

In the early 20th century, before the1950s,     5     railways were not yet in operation and road traffic was     6     (convenient), the sheepskin raft served as the most important means of transportation for residents     7     (live) along the Yellow River.

However, with the rapid development of society, the sheepskin raft has     8     (large) fulfilled its historical role in transporting people and goods. Nowadays, it can only     9     (find) along the banks of the Yellow River in some cities in Gansu province. It has become     10     tool for people to ferry on the Yellow River for sightseeing and leisure.

Beijing was once a city of bikes, the capital of a country    1    (know) as the Bicycle Kingdom, where cars were reserved for official and political business.    2    , decades of remarkable economic growth led to a huge flowing of cars in the city. Owning one became not just a marker of reaching the middle class but also a    3    (require) for marriage. As the economy boomed, autos pushed bikes off the roads,    4    (create) heavy pollution and miserable traffic.

Fortunately, now Beijing may be returning to its roots with a modern twist. Thanks to about 20 technology companies, brightly coloured shared bikes    5    (flood) Beijing since last year. Many local residents welcome the shared bikes    6    the flexibility and freedom they offer. They pick up the bikes and then ride and drop    7    off anywhere they like, locking the back wheel, with no need to find a fixed place.

Analysis in China say there are three factors    8    contribute to the sudden increase of bikes: a lot of cash looking for a home, a good idea and government support. “As the city’s population grew, traffic jams got    9    (bad).” Cai, the Ofo spokeswoman, said, “Shared bikes could solve the ‘last mile’ problem in    10    environmentally friendly way.”