Definition: In this task, you will use your knowledge about language (and common sense) to determine what element the marked number refers to. The numbers are marked with two underlines around them, like: _ number _. Your answer should be chosen from the given text, and should not contain other words.
Input: Tom Earnshaw, Copilot in B for Bertie:  Now look here , what are we going to do about our clothes ?
Frank Shelley - Observer: Yes , we 've got to get into civvies somehow .
John Glyn Haggard - Pilot in B for Bertie: Well , what 's George doing ?
Sir George Corbett, Rear Gunner in B for Bertie: I 'm swimming .
John Glyn Haggard - Pilot in B for Bertie: Where ?
Sir George Corbett, Rear Gunner in B for Bertie: In a canal .
John Glyn Haggard - Pilot in B for Bertie: Well , how do you know there is _ one _ ?
Sir George Corbett, Rear Gunner in B for Bertie: There 's always a canal in Holland . The next best thing to having civilian clothes is to have none . I 'm going to be a swimming instructionist and spy off the land .

canal