下列离子方程式书写正确的是
A.Na投入到水中: Na + H2O="===" Na+ + OH- + H2↑ |
B.AlCl3溶液中加入足量的氨水:Al3+ + 3OH-="==" Al(OH)3↓ |
C.Al2O3和NaOH溶液:Al2O3 +2OH-====2AlO2-+ H2O |
D.FeCl2溶液跟Cl2反应:Fe2++ Cl2="==" Fe3++ 2Cl- |
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 |