A:
B:
C:
D:
A. Can I read the books here?
B. We usually talk quietly in the library
C. Keep your desk clean.
D. Take turns
世界上绝大多数动植物在我国都能找到适合生长的地区,这主要是因为我国( )
我国有在元宵节燃放孔明灯(如图)祈福的风俗,孔明灯燃气的火焰温度可达300℃,但纸质(着火点约170℃)灯罩却没被点燃.原因是( )
已知△ABC的三边分别长为a、b、c,且满足(a﹣17)2+|b﹣15|+c2﹣16c+64=0,则△ABC是( )