下列实验操作与安全事故处理错误的是
| A.用试管夹从试管底由下往上夹住距离管口约三分之一处,手持试管夹长柄末端,进行加热 |
| B.制备乙酸乙酯时,将乙醇和乙酸依次加入到浓硫酸中 |
| C.把玻璃管插入橡胶塞孔时,用厚布护手,紧握用水湿润的玻璃管插入端,缓慢旋进塞孔中 |
| D.实验时不慎打破温度计水银球,用滴管将水银吸出放入水封的小瓶中,残破的温度计插入装有硫粉的广口瓶中 |
The CDs are on sale! Buy one and you get ______ completely free. 
| A. | other | B. | others | C. | one | D. | ones |
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 |