下列有关钠的叙述正确的是①钠在空气中燃烧生成氧化钠 ②金属钠可以保存在煤油中③钠与硫酸铜溶液反应,可以置换出铜 ④金属钠有强还原性⑤钠原子的最外层上只有一个电子,所以在化合物中钠的化合价显+1价
The CDs are on sale! Buy one and you get ______ completely free.
I’m sure that your letter will get______ attention. They know you’re waiting for the reply.
All the dishes in this menu, ______ otherwise stated, will serve two to three people.
The children loved their day trip, and they enjoyed the horse ride ______.
Progress______ so far very good and we are sure that the work will be finished on time.