① I can play the violin. ____ A. Boom—boom!
② Can you hear my drum? ____ B. Zing—zing!
③ Listen! It's Peter's triangle. ____ C. Ding—ding!
④ I like playing the piano. ____ D. Ting—ting!
平均放在5个书架上,每个书架放几本?
每个书架放6本,需要几个书架?
《全球通史》中描述苏俄的经济时提到“强行征用供养士兵和城市居民所必需的剩余农产品”,“几乎所有的工厂都在为前线生产”。由此可知当时苏俄采取的经济政策是( )