A:间期和末期
B:前期和末期
C:中期和后期
D:后期和前期
东南亚主要的油棕出口国家是( )
Large amounts of food ______ wasted in our school everyday, but the poor in many countries ______ no access to drinking water.
琳琳经常不吃早餐就去上学,有时会出现头晕、心慌、注意力不集中等症状,原因是他血液中哪种物质的浓度过低?( )