Fishermen and ____ (sail) sometimes claim to have seen monsters in the sea. ____ people have often laughed at stories told by seamen, it is now ____ (know) that many of these ‘monsters' which have at times been sighted are ____ (simple) strange fish. Occasionally, ____ (usual) creatures are washed to the shore, but they are rarely caught out at sea. Some time ago, however, a peculiar fish was caught near Madagascar. A small fishing boat ____ (carry) miles out to sea by the powerful fish as it pulled on the line. ____  (realize) that this was no ordinary fish, the fisherman made every effort not to damage ____ in any way. When it was eventually brought to shore, it was found to be over thirteen feet long. It had a head like a horse, big blue eyes, shinning silver skin and a bright red tail. The fish, which has since been sent to a museum ____ it is being examined by a scientist, is called an oarfish. Such creatures have rarely been seen ____ (live) by man as they live at a depth of six hundred feet.

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若﹣2a＞﹣2b，则a＜b，它的逆命题是 ____