如果你以前从未潜过水，只要试着在水底呼吸就行，一下子你就自由了，”马克说，“当你在大堡礁潜水时，感觉好像世界上一切都不存在了。

• If you've never dived before to just be able to breathe underwater, all of a sudden you're free," said Mark, " When you're underwater in the Great Barrier Reef it's like nothing else in the world.