阿伏加德罗常数约为6.02×1023mol-1,下列说法中正确的是
| A.22.4 L CH3CHO中含有的分子数约为6.02×1023 |
| B.56g铁与足量稀H2SO4充分反应,转移电子数为0.3NA |
| C.常温常压下,由6 g NO2和40 g N2O4组成的混合气体中原子总数约为3×6.02×1023 |
| D.80 g NH4NO3晶体中含有NH4+小于 6.02×1023个 |
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 |
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 |