查字典
“树”按部首查字法应查____部,再查____画,组词____
I manage to get the chance to interview Ma Yun. I am very excited.
4Al(s)+3O2(g)=2Al2O3(s) ΔH1
4Al(s)+2O3(g)=2Al2O3(s) ΔH2
3O2(g)=2O3(g) ΔH3则( )
得到这些图形要用到____