there is a bed __at_ the corner of the room,为什么用介词at

there is a bed __at_ the corner of the room,为什么用介词at There is a bed,( )and( ) opposite the bed there is a table there is a doll on the bed. There is a picture_______ the bed is there a bed toy the under There is a bed in it.What is is?翻译 There is the bed. 连词成句 is,and,a,mirror,there,bed,a 连词成句;is,there,a,a,bed,cioset.and 连词成句:is,a,picture,bed,there,over,the there is a bed in the house变一般疑问句 there is only a s_____ bed in the room? There is a jacket on the bed 改为一般疑问句 那里有床吗?英语翻译是不是Is there a bed? is,my,desk,bed,there,a,near (连词成句) there is a new bed 怎么改为复数形式? there is a ball under my bed(同义句)