A:铁牛具、牛耕的推广
B:水利工程的兴修
C:社会秩序的稳定
D:土地私有制的发展
热现象在一年四季中都很常见,下列有关热现象的说法中,正确的是
根据所给电路图(图甲),请在图乙中以笔划线代替导线将实物图补充完整.
-- Do you know ______ our Chinese National Symbol of Day (国家公祭日) is?
-- Yes, it's on December 13th. It's in memory of the people_____ were killed in Nanjing Massacre.
读下图,完成下列各题。