题目

如图8-3-2所示，玻璃管A和B下端用橡皮管相连，内装水银，A管上端封闭有某种气体，B管上端开口与大气相通，保持下端位置不变，将B管缓慢倾斜，则(    ) 图8-3-2A.A管内气体的体积增大                              B.A管内气体的体积减小C.两管的水银面高度差减小                          D.两管的水银面高度差增大句型转换 It was certain that they had done that evening. There was ________ ________ that they had done that evening.