265.
(A) So sensitive are the lips　
(B) So sensitive the lip is　
(C) Such sensitive the lip is　
(D) Such sensitive are the lips(答案A)Recent studies have shown that alcohol is the leading gateway drug for teenagers.　Gateway drugs are substances people take that 266 them to take more drugs.　Alcohol works directly on the central nervous system and alters one’s moods and limits judgment.　Since its way of altering moods (changing one’s state of mind) is generally expected and socially acceptable, oftentimes it 267 over drinking.　Habitual drinkers may find alcohol not stimulating enough 268 and want to seek other more stimulating substances. 269 a circumstance often preconditions teenagers to the possibility of taking other drugs such as marijuana, cocaine or heroin.　Another reason why alcohol is the main gateway drug is that the 270 of teenagers it can affect is very wide.　It is easily accessible in most societies and common in popular events such as sports gatherings and dinner parties.