下列反应不能用离子方程式：CO32－ + 2H+ ＝CO2 ↑ + H2O表示的是 A．Na2CO3 + 2HCl ＝ 2NaCl + CO2 ↑+ H2O B．K2CO3 + 2HNO3 ＝ 2KNO3 + CO2 ↑ + H2O C．K2CO3 + H2SO4 ＝ K2SO4
阅读理解阅读下列短文，然后从A、B、C、D四个选项中选出能回答所提问题或完成所给句子的最佳选项。Harry Potter and the Deathly Hallows By J. K.
英国君主立宪制是哪三者融为一体的混合物（ ） ①君主制 ②贵族制 ③民主制 ④共和制A．①②③ B．②③
You've just come home, after living abroad for a few years. Since you've been away, has this country changed for the better—or for the worse? If you've just arrived back in the UK after a fortnig
下图是N、M两国人口年龄金字塔结构图，关于两类国家人口合理容量的叙述正确的是( ) A．N类国家因环境人口容量潜力大而人口增长快 B．M类国家因人
One day, a young man was cleaning out his late grandfather’s belongings when he came across a bright red envelope. Written on the front were the words, To my grandson. Recognizing his grandfather's
设集合，若，则与的关系是 （ ） A． B． C． D．
已知等差数列｛an｝与｛bn｝的前n项和分别为Sn与Tn, 若, 则的值是 ( ) A B C
