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Can you think of ways to make the world greener? Here is an e____ . A couple have travelled around the world in 297 days — w____  taking any planes.

Tom Fewins and Lara Lockwood u____  78 buses, 61 trains, 34 cars, 18 boats, 6 bicycles, and even 1 elephant. They wanted to prove (证明) that t____ can still travel well without damaging (破坏) the environment. They thought they could p____ less than 3,000 kg of carbon dioxide (二氧化碳) if they didn’t travel by plane.

They spent ten months travelling 44,609 miles t____ 18 countries on land and sea. The couple’s tour b____ in June, 2008 with a two-hour bus trip to London from their home in Oxforshire. They t____ the train to Brussels and then caught a bus and train to Hamburg. The couple even r____ on an elephant for 15 miles to go through the Chinese part of the Mekong River.

The couple hoped to write a book based on their j ____ . They thought it would teach other travellers how to travel in a green way.