1．If someone is in d________， he will cry out “help”．
2．Something should be done to r________ air pollution.
3．Smoking can cause lung c________， so you'd better give it up.
4．The doctor ________ penicillin (盘尼西林) into his arm.
5．The shoppers are forbidden to sell the ________(香烟) to the people who are under 18.
