湄公河平原水稻耕作的良好自然条件包括 ( )
①土壤深厚、肥沃 ②高温多雨 ③水网密布 ④人口稠密
A:①②④
B:②③④
C:①③④
D:①②③
“I don't think it's my ________ that the window suddenly broke. I just opened it, that's all,” said the boy in tears.
埃及的耕地、人口、城市主要集中在 ( )
有些药物常被封装在用淀粉制成胶囊中服用,以避免对胃产生刺激。从淀粉在消化道内的消化特点来看,其原因是( )