一块表面已被氧化为Na2O的钠块10.8g，将其投入100g水中，产生H2 0.2g，则被氧化的钠是（ ）
| A．9.2g | B．10.6g | C．6.2g | D．4.6g |
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 |