A:K+、SO42﹣、CO32﹣
B:NH4+、Na+、SO42﹣
C:Mg2+、HCO3﹣、Cl﹣
D:Ag+、Al3+、Cl﹣
A. restaurant B. company C. library D. driver E. policeman F. policewoman
⑴ ____ ⑵ ____
⑶ ____ ⑷ ____
⑸ ____ ⑹ ____