Unit 2 In the classroom一、选择题1.Open ______ books, please!( )A.youB.yourC.on2.Are there any _______ in the schoolbag?( )A.chairB.floorC.books3.﹣ What's this?( ) It's a ________﹣.A.catB.youC.under4.﹣ _________ is the door?( ) It's brown﹣.A.How B.How many C.What c...