题目

实验室常用氢氧化钠溶液吸收氯化氢尾气，以防止环境污染。下列既能吸收尾气，又能防止溶液倒吸的装置是   答案：B22、As the bell rang, the door was pushed open and _____.   A. out ran the kids                                     B. out the kids ran   C. out did the kids run                               D. out had the kids run