You are going to read an article about the Channel Tunnel, which was recognised as one of the "Seven Wonders of the Modern World" by the American Society of Civil Engineers. Some words are missing from the text. Your task is to choose the most appropriate word from the list for each gap (1-9) in the text. You can use each word only once.

Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. Note that you will lose points if you ask for hints!
   buried      carried      dig      making      seen      that      took      use      using   

The Channel Tunnel is 31.4 miles long, (1) it the 11th longest tunnel in (2) . It has the longest undersea portion of any tunnel in the world (23.5 miles). There are actually three tunnels down there - two for trains and a smaller service tunnel (3) can be used in emergencies. Construction (4) six years (1988-1994). Englishman Graham Fagg and Frenchman Phillippe Cozette (5) out the ceremonial breakthrough on December 1, 1990. They didn't quite meet in the middle – the English side tunnelled the greater distance. Eleven special machines were used to (6) the tunnel. Each of them was as long as two football pitches. One from the British side remains (7) under the Channel. Another was sold on eBay for £39,999 in 2004. In 2014 a record 21 million passengers were transported between Britain and France (8) the tunnel – up from 7.3 million in 1995, its first full year in operation. A pet travel scheme introduced in 2000 has (9) more than one million dogs and cats travelling through the tunnel.