我国稀土矿资源丰富，品位甚高。提取稀土元素可以向含RE(RE表示稀土元素)的硫酸盐溶液中加入粉状Na2SO4，使稀土元素转入沉淀。有关的反应为(RE)2(SO4)3＋Na2SO4＋xH2O
(RE)2(SO4)3·Na2SO4·xH2O↓。下列叙述不正确的是（ ）
| A．该反应属于化合反应 |
| B．该反应属于可逆反应 |
| C．生成的产物在分类上属于复盐 |
| D．RE在化合物中的化合价为＋3 |
有西方学者认为：“近代世界赖以建立的种种发明与发现可能有一半来源于中国”。传入欧洲并对“近代世界”的到来产生了重大影响的中国科技成就是（ ）
| A．地动仪 | B．造纸术 | C．雕版印刷术 | D．罗盘针 |
I can’t leave. She told me that I ______ stay here until she comes back.
| A．can | B．must | C．will | D．may |
—— Do you mind my opening the window? It’s a bit hot in here.
—— ______ , as a matter of fact
| A．Go ahead | B．Yes, my pleasure |
C．Yes, I do | D．Come on |
It’s high time you had your hair cut ; it’s getting _______ . 
| A．too much long | B．much too long |
C．long too much | D．too long much |
My friend showed me round the town, ______ was very kind of him. 
| A．which | B．that | C．where | D．it |