A:贫富差距拉大
B:军事对抗升级
C:文化差异加大
D:政治纷争加
— Talking loudly in a library is impolite.
— In fact, we should also ________ not to cough(咳嗽) or sneeze(打喷嚏)loudly in public.
最能反映青藏高原主要自然特征的地表景观是( )