用如图装置进行实验，将液体A逐滴加人到固体B中，下列叙述正确的是
| A．若A为浓盐酸,B为KMnO4晶体，C中盛有紫色石蕊溶液，则C中熔液最终呈红色 |
| B．实验仪器D可以起到防止溶液倒吸的作用 |
| C．若A为浓氨水，B为生石灰，C中盛有AlCl3溶液，则C中溶液先产生白色沉淀后沉淀又溶解 |
| D．若A为浓H2SO4．B为Cu,C中盛有澄清石灰水，则C中溶液变浑浊 |
The CDs are on sale! Buy one and you get ______ completely free.
| A．other | B．others | C．one | D．ones ks |
I’m sure that your letter will get______ attention. They know you’re waiting for the reply. 
| A．continued | B．immediate | C．careful | D．general |
All the dishes in this menu, ______ otherwise stated, will serve two to three people. 
| A．as | B．if | C．though | D．unless |
The children loved their day trip, and they enjoyed the horse ride ______.
| A．most | B．more | C．less | D．little |
Progress______ so far very good and we are sure that the work will be finished on time.
| A．was | B．had been | C．has been | D．will be |