下列各溶液中，Na+物质的量浓度最大的是
A．1 L 0.3mol/L Na2SO4溶液 |
B．1 L 0.3mol/L NaCl溶液 |
| C．2 L 0.4mol/L NaOH溶液 | D．2 L 0.15mol/L Na3PO4溶液 |
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 |
Charles was alone at home, with_______ looking after him.
| A．someone | B．anyone | C．not one | D．no one |
It is often ______ that human beings are naturally equipped to speak.
| A．said | B．to say | C．saying | D．being said |
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 |