登革热地方性流行区的当地居民易患登革出血热的原因是()
A.遗传因素
B.气候因素
C.生活习惯
D.当地卫生条件差,有利于疾病传播
E.当地居民血液中有促进性抗体
参考答案:E
It's no use ____ to persuade him to get rid of that habit; he can't make ____. [ ]
A. trying, it
B. to try; it
C. trying; that
D. to try; that
唐代私学管理的基本特点是什么?