【简答题】You can put the book in in the bag.
【单选题】—Why do you always put this book in your backpack? —Because this book _____ my interest in the study of history. [ ]
【简答题】蛋白质能够以胶体性质在溶液中稳定存在是因为蛋白质具有 ( )和( )。
【简答题】蛋白质溶液具有胶体的性质,其分散于水中的颗粒直径约为______nm,使蛋白质溶液稳定的两因素是蛋白质分子表面的______和______。
【单选题】He put the book in the box____ the shelf.