A:Really?Thank you.
B:Sorry to hear that.
C:It doesn't matter.
将矩形纸片ABCD按如图所示的方式折叠,得到菱形AECF.若AB=3,则BC的长为____.
Look! The boy ____ (throw) some bones at the dog.
下列字形和划线字注音全部正确的一项是( )
读某大洲轮廓图, 以下别称所描述的地理事物属于该大洲的是 ( )