No matter how well you understand a foreign language, misunderstanding still exists between native speakers and you. Here is such an example. Three young Frenchmen were travelling in Britain. Though they had taken a few English lessons before their holiday, they were often in trouble because of their misunderstanding of English. One day they talked about their misfortunes   together. The first Frenchman said, "I once heard someone shout 'Look out', I put my head out of a window and a bucket   of water fell on me." The second Frenchman said, "I was once in a ship and heard the captain shouted, 'All hands on decks  ' I put my hands on the deck and someone walked on them." The third Frenchman said, "I once called early on an English friend and the maid   who came to the door said, 'He's not up yet' When I went again for him, she said, 'He's not down yet'. I said, 'If he's not up and he's not down, where is he?' She said, 'He's still upstairs now. When I told you he was not up I meant he had not got up yet, so he has not come downstairs by now' " When someone is calling "look out" to you,he probably wants you to   _  .
put your head out of the window go away receive a bucket of water be careful