541
2901
30
401
207
199
109
1999
11
111
200
____
下列地区中,多为发达国家的是( )
下列词语中划线字的读音,全都正确的一组是( )
在平面直角坐标系中,抛物线C1:y=ax2+4x+4a(0<a<2)
Our headmaster isn't in his office. I can't find him anywhere. Did you notice him ______ the office?